Harley-Davidson motorcycles are known for their power, durability, and iconic design. But even the most dependable machines can run into issues over time. That’s where Diagnostic Trouble Codes (DTC) come into play, helping you identify and resolve problems before they become serious. Whether you’re a hands-on DIY rider or simply want to understand what that check engine light means, this guide breaks it all down.
Table of Contents
What Are Harley Davidson DTC Codes?
DTC, or Diagnostic Trouble Codes, are a set of alphanumeric codes stored by your motorcycle’s Electronic Control Module (ECM) when it detects a fault. These codes act like a built-in diagnostic system, helping you or your mechanic pinpoint where something has gone wrong, whether in the engine, electrical system, transmission, or sensors.
Each code has a specific meaning. Understanding these codes can save time and prevent guesswork when troubleshooting problems.
DTC codes often show up as warnings or symbols on your instrument panel before you even connect a diagnostic tool. To better understand the components behind these alerts, check out our guide on Harley Davidson instruments.
How DTC Codes Work
Modern Harley-Davidson bikes constantly monitor their systems using sensors. When an irregularity is found, like an unexpected voltage reading or abnormal engine behavior, the ECM logs a DTC. These codes are grouped into four main categories:
- P-codes: Powertrain (engine, transmission)
- B-codes: Body (lighting, instruments, etc.)
- C-codes: Chassis (ABS, suspension)
- U-codes: Network (communication errors between modules)
How to Read Harley DTC Codes
There are two primary ways to access these codes:
- Using a Diagnostic Tool
Plug in a compatible diagnostic scanner, such as Harley’s Digital Technician, ThunderMax ECM tuner, or a standard OBD-II tool, to your bike’s diagnostic port. The tool will read and display active or stored DTCs. - Manual Method (for some models)
Some Harleys allow you to access stored codes via the odometer display by toggling through the menu with the ignition key sequence. Refer to your owner’s manual for steps specific to your model.
Understanding and Interpreting the Codes
Each DTC is made up of a letter and four numbers. For example:
- B1300: Radio Voltage High
- P0261: Fuel injector low/open (front)
To interpret a code, you can:
- Refer to the Harley Davidson DTC code chart (listed below).
- Use a scanner that automatically decodes them.
- Download the full PDF/Excel lookup table (link below).
The Priority Order
Each DTC is assigned a priority level that indicates the recommended order for diagnosis. When multiple codes are present, always begin with the one marked as highest priority to ensure accurate and efficient troubleshooting.
Common Harley Davidson DTC Codes and What They Mean
Here’s a list of frequently encountered trouble codes and their meanings:
| DTC | Priority Order | Meaning | Solution |
|---|---|---|---|
| B1103 | 47 | LHCM internal error | SWITCH DIAGNOSTICS |
| B1153 | 46 | RHCM internal error | SWITCH DIAGNOSTICS |
| B1200 | 37 | IM internal fault | NO INSTRUMENT POWER DIAGNOSTICS |
| B1210 | 176 | Fuel level sender shorted low/open | FUEL GAUGE AND SENDER DIAGNOSTICS |
| B1211 | 182 | Fuel level sender shorted high | FUEL GAUGE AND SENDER DIAGNOSTICS |
| B1212 | 175 | Fuel signal low | FUEL GAUGE AND SENDER DIAGNOSTICS |
| B1213 | 176 | Fuel signal high | FUEL GAUGE AND SENDER DIAGNOSTICS |
| B1300 | 340 | Radio voltage high | AUDIO VOLTAGE DIAGNOSTICS |
| B1301 | 341 | Radio voltage low | AUDIO VOLTAGE DIAGNOSTICS |
| B1302 | 342 | Faceplate home button stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1303 | 343 | Faceplate favorite button stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1304 | 344 | Faceplate navigation button stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1305 | 345 | Faceplate power/mute button stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1306 | 399 | Rear hand controls shorted high | REAR AUDIO CONTROL DIAGNOSTICS |
| B1307 | 400 | Rear hand controls shorted low | REAR AUDIO CONTROL DIAGNOSTICS |
| B1308 | 401 | Rear volume up button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1309 | 402 | Rear volume down button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1310 | 403 | Rear mode button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1311 | 404 | Rear PTT button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1312 | 405 | Rear tune up button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1313 | 406 | Rear tune down button stuck | REAR AUDIO CONTROL DIAGNOSTICS |
| B1314 | 346 | LHCM VR PTT button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1315 | 347 | LHCM up button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1316 | 348 | LHCM left button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1317 | 349 | LHCM center button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1318 | 350 | LHCM right button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1319 | 351 | LHCM down button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1320 | 352 | RHCM info button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1321 | 353 | RHCM up button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1322 | 354 | RHCM left button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1323 | 355 | RHCM center button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1324 | 356 | RHCM right button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1325 | 357 | RHCM down button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1326 | 358 | RHCM CB squelch up button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1327 | 359 | RHCM CB PTT button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| B1328 | 360 | RHCM CB squelch down button stuck | FRONT HAND CONTROLS DIAGNOSTICS |
| 81329 | 361 | Faceplate preset button 1 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1330 | 362 | Faceplate preset button 2 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1331 | 363 | Faceplate preset button 3 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1332 | 364 | Faceplate preset button 4 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| 81333 | 365 | Faceplate preset button 5 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1334 | 366 | Faceplate preset button 6 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1335 | 367 | Faceplate preset button 7 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1336 | 368 | Faceplate preset button 8 stuck | FACEPLATE BUTTON DIAGNOSTICS |
| B1337 | 369 | Front left speaker shorted together | FRONT SPEAKER DIAGNOSTICS |
| B1338 | 370 | Front left speaker open | FRONT SPEAKER DIAGNOSTICS |
| B1339 | 371 | Front left speaker shorted low | FRONT SPEAKER DIAGNOSTICS |
| B1340 | 372 | Front left speaker shorted high | FRONT SPEAKER DIAGNOSTICS |
| B1341 | 373 | Rear left speaker shorted together | REAR SPEAKER DIAGNOSTICS |
| B1342 | 374 | Rear left speaker open | REAR SPEAKER DIAGNOSTICS |
| B1343 | 375 | Rear left speaker shorted low | REAR SPEAKER DIAGNOSTICS |
| B1344 | 376 | Rear left speaker shorted high | REAR SPEAKER DIAGNOSTICS |
| B1345 | 377 | Front right speaker shorted together | FRONT SPEAKER DIAGNOSTICS |
| B1346 | 378 | Front right speaker open | FRONT SPEAKER DIAGNOSTICS |
| B1347 | 379 | Front right speaker shorted low | FRONT SPEAKER DIAGNOSTICS |
| B1348 | 380 | Front right speaker shorted high | FRONT SPEAKER DIAGNOSTICS |
| B1349 | 381 | Rear right speaker shorted together | REAR SPEAKER DIAGNOSTICS |
| B1350 | 382 | Rear right speaker open | REAR SPEAKER DIAGNOSTICS |
| B1351 | 383 | Rear right speaker shorted low | REAR SPEAKER DIAGNOSTICS |
| B1352 | 384 | Rear right speaker shorted high | REAR SPEAKER DIAGNOSTICS |
| B1353 | 385 | Speaker output | DC offset DTC B1353 |
| B1354 | 386 | GPS antenna open | SECURITY ANTENNA DIAGNOSTICS |
| B1355 | 387 | GPS antenna shorted low | SECURITY ANTENNA DIAGNOSTICS |
| B1356 | 388 | SDARS antenna open | SECURITY ANTENNA DIAGNOSTICS |
| B1357 | 389 | SDARS antenna shorted | SECURITY ANTENNA DIAGNOSTICS |
| B1358 | 390 | Front left headset shorted high | HEADSET DTCS |
| B1359 | 391 | Front right headset shorted high | HEADSET DTCS |
| B1360 | 392 | Front left headset shorted low | HEADSET DTCS |
| B1361 | 393 | Front right headset shorted low | HEADSET DTCS |
| B1362 | 394 | Rear left headset shorted high | HEADSET DTCS |
| B1363 | 395 | Rear right headset shorted high | HEADSET DTCS |
| B1364 | 396 | Rear left headset shorted low | HEADSET DTCS |
| B1365 | 397 | Rear right headset shorted low | HEADSET DTCS |
| B1366 | 398 | Internal thermal shutdown error | DTC 81366 |
| B1367 | 451 | WIM fault detected | Code used to support P&A parts. |
| B1401 | 407 | Amp voltage low | AUDIO VOLTAGE DIAGNOSTICS |
| B1402 | 408 | Amp voltage high | AUDIO VOLTAGE DIAGNOSTICS |
| B1403 | 409 | Speaker output DC offset | AMPLIFIER 1 DTCS |
| B1404 | 410 | Internal thermal shutdown error | AMPLIFIER 1 DTCS |
| B1405 | 427 | EQ correlation error | AUDIO SYSTEM SYMPTOMS |
| B1406 | 428 | Invalid or missing EQ | AUDIO SYSTEM SYMPTOMS |
| B1410 | 411 | Channel 1 speaker open | AMPLIFIER 1 DTCS |
| B1411 | 412 | Channel 1 speaker shorted low | AMPLIFIER 1 DTCS |
| B1412 | 413 | Channel 1 speaker shorted high | AMPLIFIER 1 DTCS |
| B1413 | 414 | Channel 1 speaker shorted together | AMPLIFIER 1 DTCS |
| B1420 | 415 | Channel 2 speaker open | AMPLIFIER 1 DTCS |
| B1421 | 416 | Channel 2 speaker shorted low | AMPLIFIER 1 DTCS |
| B1422 | 417 | Channel 2 speaker shorted high | AMPLIFIER 1 DTCS |
| B1423 | 418 | Channel 2 speaker shorted together | AMPLIFIER 1 DTCS |
| B1430 | 419 | Channel 3 speaker open | AMPLIFIER 1 DTCS |
| B1431 | 420 | Channel 3 speaker shorted low | AMPLIFIER 1 DTCS |
| B1432 | 421 | Channel 3 speaker shorted high | AMPLIFIER 1 DTCS |
| B1433 | 422 | Channel 3 speaker shorted together | AMPLIFIER 1 DTCS |
| B1440 | 423 | Channel 4 speaker open | AMPLIFIER 1 DTCS |
| B1441 | 424 | Channel 4 speaker shorted low | AMPLIFIER 1 DTCS |
| B1442 | 425 | Channel 4 speaker shorted high | AMPLIFIER 1 DTCS |
| B1443 | 426 | Channel 4 speaker shorted together | AMPLIFIER 1 DTCS |
| B2102 | 4 | System power output shorted high | SYSTEM POWER CIRCUIT DIAGNOSTICS |
| B2103 | 5 | System power output shorted low | SYSTEM POWER CIRCUIT DIAGNOSTICS |
| B2104 | 6 | System power output over- loaded | SYSTEM POWER CIRCUIT DIAGNOSTICS |
| B2106 | 257 | L4 open output | HEADLAMP DIAGNOSTICS |
| B2107 | 225 | L4 output shorted high | HEADLAMP DIAGNOSTICS |
| B2108 | 226 | L4 output shorted low | HEADLAMP DIAGNOSTICS |
| B2109 | 227 | L4 output overloaded | HEADLAMP DIAGNOSTICS |
| B2112 | 132 | ACC output shorted high | ACC CIRCUIT DIAGNOSTICS |
| B2113 | 134 | ACC output shorted low | ACC CIRCUIT DIAGNOSTICS |
| B2114 | 136 | ACC output overloaded | ACC CIRCUIT DIAGNOSTICS |
| B2116 | 92 | Fuel pump output open | FUEL PUMP DIAGNOSTICS |
| B2117 | 93 | Fuel pump output shorted high | FUEL PUMP DIAGNOSTICS |
| B2118 | 94 | Fuel pump output shorted low | FUEL PUMP DIAGNOSTICS |
| B2119 | 95 | Fuel pump output overloaded | FUEL PUMP DIAGNOSTICS |
| B2121 | 58 | Starter output open | STARTER OUTPUT DTCS |
| B2122 | 59 | Starter output shorted high | STARTER OUTPUT DTCS |
| B2123 | 60 | Starter output shorted low | STARTER OUTPUT DTCS |
| B2124 | 61 | Starter output overloaded | STARTER OUTPUT DTCS |
| B2127 | 243 | E4 output shorted high | HORN DIAGNOSTICS |
| B2128 | 244 | E4 output shorted low | HORN DIAGNOSTICS |
| B2129 | 245 | E4 output overloaded | HORN DIAGNOSTICS |
| B2131 | 233 | High beam open output | HEADLAMP DIAGNOSTICS |
| B2132 | 234 | High beam output shorted high | HEADLAMP DIAGNOSTICS |
| B2133 | 235 | High beam output shorted low | HEADLAMP DIAGNOSTICS |
| B2134 | 236 | High beam output overloaded | HEADLAMP DIAGNOSTICS |
| B2136 | 229 | Low beam open output | HEADLAMP DIAGNOSTICS |
| B2137 | 230 | Low beam output shorted high | HEADLAMP DIAGNOSTICS |
| B2138 | 231 | Low beam output shorted low | HEADLAMP DIAGNOSTICS |
| B2139 | 232 | Low beam output overloaded | HEADLAMP DIAGNOSTICS |
| B2141 | 207 | Left front turn signal output open | FRONT TURN SIGNAL DIAGNOSTICS |
| B2143 | 214 | Left front turn signal output shorted low | FRONT TURN SIGNAL DIAGNOST ICS |
| B2144 | 215 | Left front turn signal output overloaded | FRONT TURN SIGNAL DIAGNOST ICS |
| B2146 | 216 | Right front turn signal output open | FRONT TURN SIGNAL DIAGNOSTICS |
| B2148 | 217 | Right front turn signal output shorted low | FRONT TURN SIGNAL DIAGNOST ICS |
| B2149 | 218 | Right front turn signal output overloaded | FRONT TURN SIGNAL DIAGNOST ICS |
| B2151 | 219 | Left rear turn signal output open | REAR TURN SIGNAL DIAGNOSTICS |
| B2153 | 220 | Left rear turn signal output shorted low | REAR TURN SIGNAL DIAGNOST ICS |
| B2154 | 221 | Left rear turn signal output overloaded | REAR TURN SIGNAL DIAGNOSTICS |
| B2156 | 222 | Right rear turn signal output open | REAR TURN SIGNAL DIAGNOSTICS |
| B2158 | 223 | Right rear turn signal output shorted low | REAR TURN SIGNAL DIAGNOST ICS |
| B2159 | 224 | Right rear turn signal output overloader | REAR TURN SIGNAL DIAGNOST ICS |
| B2161 | 198 | Brake lamp output open | STOP LAMP DIAGNOSTICS |
| B2163 | 199 | Brake lamp output shorted low | STOP LAMP DIAGNOSTICS |
| B2164 | 200 | Brake lamp output overloaded | STOP LAMP DIAGNOSTICS |
| B2168 | 172 | Running lights output shorted low | RUNNING LAMP DIAGNOSTICS |
| B2169 | 173 | Running lights output over-loaded | RUNNING LAMP DIAGNOSTICS |
| B2172 | 237 | H2 output shorted high | ALARM DIAGNOSTICS |
| B2173 | 238 | H2 output shorted low | ALARM DIAGNOSTICS |
| B2176 | 239 | Security antenna output open | SECURITY ANTENNA DIAGNOSTICS |
| B2177 | 240 | Security antenna output shorted high | SECURITY ANTENNA DIAGNOSTICS |
| B2178 | 241 | Security antenna output shorted low | SECURITY ANTENNA DIAGNOSTICS |
| B2183 | 249 | G2 output shorted low | ADDITIONAL OUTPUT DIAGNOSTICS |
| B2188 | 254 | G3 output shorted low | ADDITIONAL OUTPUT DIAGNOSTICS |
| B2193 | 257 | H4 output shorted low | ADDITIONAL OUTPUT DIAGNOSTICS |
| B2198 | 259 | H3 output shorted low | ADDITIONAL OUTPUT DIAGNOSTICS |
| B2201 | 52 | IGN switch off w/VSS | IGN SWITCH DIAGNOSTICS |
| B2202 | 53 | Ignition switch accy with vehicle speed | IGN SWITCH DIAGNOSTICS |
| B2203 | 50 | Ignition switch input shorted low | IGN SWITCH DIAGNOSTICS |
| B2206 | 51 | Run/stop switch input open/shorted high | ENGINE STOP SWITCH DIAGNOSTICS |
| B2208 | 54 | Run/stop switch input shorted low | ENGINE STOP SWITCH DIAGNOSTICS |
| B2210 | 55 | Run/stop switch inputs open both | SWITCH DIAGNOSTICS |
| B2212 | 56 | Run/stop switch inputs both closed | SWITCH DIAGNOSTICS |
| B2218 | 131 | Neutral switch shorted low | NEUTRAL SWITCH DIAGNOSTICS |
| B2223 | 197 | Rear brake switch shorted low (light on) | STOP LAMP DIAGNOSTICS |
| B2226 | 247 | BAS input open | BCM not configured properly. |
| B2228 | 250 | BAS input shorted low | BCM not configured properly. |
| B2231 | 312 | Fork locked w/VSS | BCM not configured properly. This DTC should only apply to CVO models. |
| B2232 | 313 | Fork lock shorted high | BCM not configured properly. This DTC should only apply to CVO models. |
| B2233 | 314 | Fork lock shorted low | BCM not configured properly. This DTC should only apply to CVO models. |
| B2234 | 315 | Fork lock detected w/option disabled | BCM not configured properly. This DTC should only apply to CVO models. |
| B2235 | 316 | Fork lock configuration invalid | BCM not configured properly. This DTC should only apply to CVO models. |
| B2250 | 128 | Clutch switch stuck | SWITCH DIAGNOSTICS |
| B2251 | 242 | Horn switch stuck | SWITCH DIAGNOSTICS |
| B2252 | 437 | High beam switch stuck | SWITCH DIAGNOSTICS |
| B2253 | 228 | FTP switch stuck | SWITCH DIAGNOSTICS |
| B2254 | 203 | Left turn switch stuck | SWITCH DIAGNOSTICS |
| B2255 | 246 | Trip switch stuck | Trip Odometer Functions Inoperative, DTC 82255 |
| B2256 | 208 | LHCM police siren power switch stuck | BCM not configured properly. This DTC should only apply to Police models. |
| B2257 | 209 | LHCM police siren wail power switch stuck | BCM not configured properly. This DTC should only apply to Police models. |
| B2258 | 210 | LHCM police siren yelp switch stuck | BCM not configured properly. This DTC should only apply to Police models. |
| B2260 | 57 | Start switch stuck | SWITCH DIAGNOSTICS |
| B2261 | 204 | Right switch stuck turn | SWITCH DIAGNOSTICS |
| B2262 | 196 | Front switch stuck brake | SWITCH DIAGNOSTICS |
| B2263 | 202 | Hazard switch stuck | SWITCH DIAGNOSTICS |
| B2264 | 211 | RHCM police lights power switch stuck | BCM not configured properly. This DTC should only apply to Police models. |
| B2265 | 212 | RHCM police lights front switch stuck | BCM not configured properly. This DTC should only apply to Police models. |
| B2266 | 213 | RHCM police lights rear switch stuck | BCM not configured properly. This DTCshould only apply to Police models. |
| B2270 | 27 | BCM internal error | SWITCH DIAGNOSTICS |
| B2271 | 26 | BCM voltage low | BCM VOLTAGE DIAGNOSTICS |
| B2272 | 33 | BCM/IM voltage high | BCM VOLTAGE DIAGNOSTICS |
| B2274 | 49 | Constant battery line error | Odometer Self-Diagnostic Inoperative: DTC 00001, 00002, U0011, B2274 |
| C0562 | 38 | ABS voltage low | ABS VOLTAGE DIAGNOSTICS |
| C0563 | 40 | ABS voltage high | ABS VOLTAGE DIAGNOSTICS |
| C1014 | 183 | ABS ECU relay error | INTERNAL FAULT DIAGNOSTICS |
| C1021 | 191 | ABS front WSS always zero | WSS DIAGNOSTICS |
| C1023 | 192 | ABS rear WSS always zero | WSS DIAGNOSTICS |
| C1025 | 194 | ABS front wheel speed intermittent | WSS DIAGNOSTICS |
| C1027 | 195 | ABS rear wheel speed intermittent | WSS DIAGNOSTICS |
| C1029 | 193 | ABS wheel speed difference too high | WSS DIAGNOSTICS |
| C1032 | 189 | ABS front wheel speed circuit open shorted | WSS DIAGNOSTICS |
| C1034 | 190 | ABS rear wheel speed circuit open shorted | WSS DIAGNOSTICS |
| C1040 | 184 | ABS pump/motor error | INTERNAL FAULT DIAGNOSTICS |
| C1055 | 39 | ABS ECU internal error | INTERNAL FAULT DIAGNOSTICS |
| C1061 | 185 | ABS front apply solenoid circuit open/high resistance | INTERNAL FAULT DIAGNOSTICS |
| C1062 | 187 | ABS front release solenoid circuit open/high resistance | INTERNAL FAULT DIAGNOSTICS |
| C1065 | 186 | ABS rear apply solenoid circuit open/high resistance | INTERNAL FAULT DIAGNOSTICS |
| C1066 | 188 | ABS rear release solenoid circuit open/high resistance | INTERNAL FAULT DIAGNOSTICS |
| C1071 | 283 | Rear prime valve error | INTERNAL FAULT DIAGNOSTICS |
| C1072 | 284 | Rear isolation valve error | INTERNAL FAULT DIAGNOSTICS |
| C1073 | 285 | Front isolation valve error | INTERNAL FAULT DIAGNOSTICS |
| C1074 | 286 | Front prime valve error | INTERNAL FAULT DIAGNOSTICS |
| C1075 | 287 | Front linked inlet valve error | INTERNAL FAULT DIAGNOSTICS |
| C1076 | 288 | Front linked outlet valve error | INTERNAL FAULT DIAGNOSTICS |
| C1077 | 289 | Front circuit pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1078 | 290 | Rear circuit pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1081 | 291 | Front master pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1082 | 292 | Front master pressure sensor offset error | INTERNAL FAULT DIAGNOSTICS |
| C1083 | 293 | Front wheel pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1084 | 294 | Front wheel pressure sensor offset error | INTERNAL FAULT DIAGNOSTICS |
| C1085 | 295 | Rear master pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1086 | 296 | Rear master pressure sensor offset error | INTERNAL FAULT DIAGNOSTICS |
| C1087 | 297 | Rear wheel pressure sensor error | INTERNAL FAULT DIAGNOSTICS |
| C1088 | 298 | Rear wheel pressure sensor offset error | INTERNAL FAULT DIAGNOSTICS |
| C1089 | 299 | Pressure sensor external supply error | INTERNAL FAULT DIAGNOSTICS |
| C1159 | 43 | ABS invalid stored | VIN INVALID VIN DIAGNOSTICS |
| C1178 | 41 | ABS no VIN received from | ECM INVALID VIN DIAGNOSTICS |
| C1184 | 42 | ABS invalid VIN from | ECM INVALID VIN DIAGNOSTICS |
| C1195 | 266 | Wake up error | INTERNAL FAULT DIAGNOSTICS |
| P0031 | 153 | Front HO2S open low | HO2S DIAGNOSTICS |
| P0032 | 156 | Front HO2S shorted high | HO2S DIAGNOSTICS |
| P0051 | 154 | Rear HO2S open low | HO2S DIAGNOSTICS |
| P0052 | 155 | Rear HO2S shorted high | HO2S DIAGNOSTICS |
| P0072 | 112 | AAT sensor low | AAT SENSOR DIAGNOSTICS |
| P0073 | 113 | AAT sensor high open | MT SENSOR DIAGNOSTICS |
| P0107 | 100 | MAP sensor failed low open | TMAP SENSOR DIAGNOSTICS |
| P0108 | 101 | MAP sensor failed high/open port | TMAP SENSOR DIAGNOSTICS |
| P0112 | 123 | IAT sensor shorted low | TMAP SENSOR DIAGNOSTICS |
| P0113 | 125 | IAT sensor high open | TMAP SENSOR DIAGNOSTICS |
| P0117 | 102 | ET sensor shorted low | ET SENSOR DIAGNOSTICS |
| P0118 | 107 | ET sensor high open | ET SENSOR DIAGNOSTICS |
| P0120 | 76 | TPS 1 range error | TCA DIAGNOSTICS |
| P0122 | 74 | TPS 1 low | TCA DIAGNOSTICS |
| P0123 | 75 | TPS 1 high open | TCA DIAGNOSTICS |
| P0131 | 157 | 02 sensor low/engine lean (front) | HO2S DIAGNOSTICS |
| P0132 | 159 | Engine running rich (front) | HO2S DIAGNOSTICS |
| P0134 | 161 | Oxygen sensor high/open (front) | HO2S DIAGNOSTICS |
| P0151 | 158 | 02 sensor low/engine lean (rear) | HO2S DIAGNOSTICS |
| P0152 | 160 | Engine running rich (rear) | HO2S DIAGNOSTICS |
| P0154 | 162 | 02 sensor high/open (rear) | HO2S DIAGNOSTICS |
| P0220 | 79 | TPS 2 range error | TCA DIAGNOSTICS |
| P0222 | 77 | TPS 2 open low | TCA DIAGNOSTICS |
| P0223 | 78 | TPS 2 high | TCA DIAGNOSTICS |
| P0261 | 96 | Fuel injector low/open (front) | FUEL INJECTOR DIAGNOSTICS |
| P0262 | 97 | Fuel injector shorted high (front) | FUEL INJECTOR DIAGNOSTICS |
| P0264 | 98 | Fuel injector low/open (rear) | FUEL INJECTOR DIAGNOSTICS |
| P0265 | 99 | Fuel injector shorted high (rear) | FUEL INJECTOR DIAGNOSTICS |
| P0325 | 139 | Knock sensor front open circuit | KNOCK SENSOR DIAGNOSTICS |
| P0327 | 140 | Knock sensor front circuit low | KNOCK SENSOR DIAGNOSTICS |
| P0328 | 141 | Knock sensor front circuit high | KNOCK SENSOR DIAGNOSTICS |
| P0330 | 142 | Knock sensor rear open circuit | KNOCK SENSOR DIAGNOSTICS |
| P0332 | 143 | Knock sensor rear circuit low | KNOCK SENSOR DIAGNOSTICS |
| P0333 | 144 | Knock sensor rear circuit high | KNOCK SENSOR DIAGNOSTICS |
| P0371 | 65 | CKP sensor wrong number of pulses | CKP SENSOR DIAGNOSTICS |
| P0374 | 64 | CKP sensor no pulses | CKP SENSOR DIAGNOSTICS |
| P0444 | 147 | Purge solenoid low open | PURGE SOLENOID DIAGNOSTICS |
| P0445 | 148 | Purge solenoid shorted high | PURGE SOLENOID DIAGNOSTICS |
| P0462 | 174 | Fuel sender shorted low | FUEL GAUGE AND SENDER DIAGNOSTICS |
| P0463 | 175 | Fuel sender shorted high/open | FUEL GAUGE AND SENDER DIAGNOSTICS |
| P0502 | 137 | VSS failed low | PURGE SOLENOID DIAGNOSTICS |
| P0503 | 138 | VSS | failed high VSS DIAGNOSTICS |
| P0505 | 148 | Idle speed control - unstable | IDLE SPEED CONTROL DIAGNOSTICS |
| P0522 | 168 | Engine oil pressure sensor/switch shorted low | INDICATOR LAMPS |
| P0523 | 169 | Engine oil pressure sensor/switch shorted high open | INDICATOR LAMPS |
| P0562 | 127 | ECM voltage low BATTERY | AND SYSTEM VOLTAGE DIAGNOSTICS |
| P0572 | 202 | Brake switch low | BRAKE SWITCH DIAGNOSTICS |
| P0577 | 163 | Cruise control | input error Cruise Control |
| P0603 | 29 | ECM EEPROM memory error | ECM INTERNAL DIAGNOSTICS |
| P0605 | 28 | ECM FLASH memory error | ECM INTERNAL DIAGNOSTICS |
| P0641 | 62 | 5 Volt reference out of range | 5V REFERENCE DIAGNOSTICS |
| P0651 | 63 | 5 Volt reference 2 out of range | 5V REFERENCE DIAGNOSTICS |
| P0693 | 119 | Chassis fan control circuit shorted low | CHASSIS FAN DIAGNOSTICS |
| P0694 | 120 | Chassis fan control circuit shorted high | CHASSIS FAN DIAGNOSTICS |
| P1009 | 32 | VTD disabled fuel due to bad password | DTC P1009 |
| P1017 | 103 | ET indicates overheating | DTC P1017 |
| P1019 | 106 | ECT difference (high temp) | ECT SENSOR DIAGNOSTICS |
| P1270 | 67 | TGS 2 ND validation error | DTC P1270 |
| P1501 | 166 | JSS low | JSS DIAGNOSTICS |
| P1502 | 167 | JSS high open | JSS DIAGNOSTICS |
| P1505 | 445 | Power limit violation | HESITATION OR LOSS OF POWER |
| P1510 | 447 | ETC limited performance mode | ETC MANAGEMENT DIAGNOSTICS |
| P1511 | 448 | ETC power management mode | ETC MANAGEMENT DIAGNOSTICS |
| P1512 | 449 | ETC forced idle mode | ETC MANAGEMENT DIAGNOSTICS |
| P1514 | 87 | ETC airflow error | ETC ERROR DIAGNOSTICS |
| P1600 | 66 | ETC watchdog error | ETC ERROR DIAGNOSTICS |
| P1655 | 164 | ACR solenoid open low | ACR Diagnostics |
| P1656 | 165 | ACR solenoid shorted high | ACR Diagnostics |
| P1691 | 115 | Cooling fan left low open | COOLING FAN DIAGNOSTICS |
| P1692 | 116 | Cooling fan left shorted high | COOLING FAN DIAGNOSTICS |
| P1693 | 117 | Cooling fan right low open | COOLING FAN DIAGNOSTICS |
| P1694 | 118 | Cooling fan right shorted high | COOLING FAN DIAGNOSTICS |
| P2100 | 82 | ETC driver open circuit | ETC ACTUATOR DIAGNOSTICS |
| P2101 | 83 | ETC actuation error | ETC ACTUATOR DIAGNOSTICS |
| P2102 | 84 | ETC driver shorted low | ETC ACTUATOR DIAGNOSTICS |
| P2103 | 85 | ETC driver shorted high | ETC ACTUATOR DIAGNOSTICS |
| P2105 | 446 | ETC forced shutdown mode | DTC P2105, P2107 |
| P2107 | 68 | ETC driver internal error | DTC P2105, P2107 |
| P2119 | 81 | ETC actuator return error | DTC P2119 |
| P2122 | 69 | TGS 1 low/open | TGS DIAGNOSTICS |
| P2123 | 70 | TGS 1 high | TGS DIAGNOSTICS |
| P2127 | 71 | TGS 2 low/open | TGS DIAGNOSTICS |
| P2128 | 72 | TGS 2 high | TGS DIAGNOSTICS |
| P2135 | 80 | TPS correlation error | CORRELATION ERROR DIAGNOSTICS |
| P2138 | 73 | TGS correlation error | CORRELATION ERROR DIAGNOSTICS |
| P2176 | 86 | ETC zero position learning error | DTC P2176 |
| P2184 | 121 | ECT sensor low | ECT SENSOR DIAGNOSTICS |
| P2185 | 122 | ECT sensor high | ECT SENSOR DIAGNOSTICS |
| P2300 | 88 | Ignition coil driver low/open (front) | IGN COIL DRIVER DIAGNOSTICS |
| P2301 | 89 | Ignition coil driver shorted high (front) | IGN COIL DRIVER DIAGNOSTICS |
| P2303 | 90 | Ignition coil driver low/open (rear) | IGN COIL DRIVER DIAGNOSTICS |
| P2304 | 91 | Ignition coil driver shorted high (rear) | IGN COIL DRIVER DIAGNOSTICS |
| P2602 | 104 | Coolant pump "A" control circuit low | COOLING PUMP DIAGNOSTICS |
| P2603 | 105 | Coolant pump "A" control circuit high | COOLING PUMP DIAGNOSTICS |
| U0001 | 1 | CAN BUS error | Odometer Self-Diagnostic Inoperative: DTC 00001, 00002, U0011, B2274 |
| U0002 | 16 | CAN comm bus perf error | Odometer Self Diagnostic Inoperative: DTC 00001, 00002, U0011, 82274 |
| U0003 | 13 | Network management monitoring | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0011 | 2 | CAN bus low shorted to CAN bus high | Odometer Self-Diagnostic Inoperative: DTC 00001, 00002, 00011, B2274 |
| U0100 | 7 | Lost comm w/ECM | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0121 | 11 | Lost comm w/ABS | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0140 | 3 | Lost comm w/BCM | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0141 | 9 | Lost comm w/LHCM | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0142 | 8 | Lost comm w/RHCM | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0156 | 10 | Lost comm w/speedo | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0158 | 180 | Lost comm w/fuel gauge | SECONDARY COMMUNICATION DIAGNOSTICS |
| U0159 | 181 | Lost comm w/volt gauge | SECONDARY COMMUNICATION DIAGNOSTICS |
| U0160 | 179 | Lost comm w/fuel and volt gauges | SECONDARY COMMUNICATION DIAGNOSTICS |
| U0184 | 323 | Lost comm w/radio | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U0185 | 325 | Lost comm w/AMP | 1 AMP COMMUNICATION DIAGNOSTICS |
| U0186 | 326 | Lost comm w/AMP | 2 AMP COMMUNICATION DIAGNOSTICS |
| U0187 | 20 | Lost comm w/AMP | 3 AMP COMMUNICATION DIAGNOSTICS |
| U0188 | 21 | Lost comm w/AMP | 4 AMP COMMUNICATION DIAGNOSTICS |
| U0300 | 15 | Internal control module software incompatibility | NO VEHICLE POWER OR LOST COMMUNICATION DTCS |
| U1302 | 324 | ACC bus pert error | SECONDARY COMMUNICATION DIAGNOSTICS |
| U1401 | 331 | Lost comm w CB | SECONDARY COMMUNICATION DIAGNOSTICS |
| U1401 | 331 | Lost comm w CB | COMMUNICATION DIAGNOSTICS |
| U1405 | 450 | ACC bus lost comm w/ WIM | Code used to support P&A parts |
Troubleshooting Common DTC Issues
Engine-Related
Transmission
Electrical and Sensors
How to Reset Harley DTC Codes
Once the problem is fixed, the DTC must be cleared. Here’s how:
- Via Diagnostic Tool: Most scanners include a “clear codes” function.
- Manual Reset: On some bikes, you can reset codes by cycling the ignition in a specific sequence (check your owner’s manual).
Always ensure the root cause is fixed before clearing codes, otherwise, the code may return.
Preventing DTCs With Routine Maintenance
DTCs often result from minor issues that regular maintenance can prevent. Stay ahead of problems by:
- Inspecting spark plugs and fuel injectors regularly.
- Checking sensor wiring and battery terminals for corrosion or loose connections.
- Ensuring lights, exhaust, and electrical systems are functioning properly.
System Abbreviations Cheat Sheet
Understanding abbreviations used in DTC can make decoding much easier. Here’s a small reference:
| Abbreviation | Full Term | Alias / Nickname | Utility (Summary) | Year Introduced | Category |
|---|---|---|---|---|---|
| ABS | Anti-Lock Braking System | Anti-Lock Brakes | Prevents wheel lockup during braking to improve safety and control | Early 2000s | Braking System |
| ACR | Automatic Compression Release | Compression Release | Eases engine starting by reducing cylinder compression | 1990s | Engine System |
| AFR | Air Fuel Ratio | Air-Fuel Mixture | Measures ratio of air to fuel for optimal combustion | N/A | Engine System |
| AIS | Active Intake Solenoid | Intake Solenoid | Controls airflow into the engine for efficiency | 2000s | Engine/Air Intake |
| ATS | Air Temperature Sensor | Air Temp Sensor | Monitors incoming air temperature for engine tuning | 1990s | Engine Sensors |
| BAS | Bank Angle Sensor | Tilt Sensor | Detects bike lean angle for safety and control functions | 2000s | Safety/Engine |
| BCM | Body Control Module | Body Control Unit (BCU) | Manages electrical systems like lights and indicators | 2000s | Electronics |
| CAN | Controller Area Network | CAN Bus | Enables communication between electronic modules | 2000s | Communication |
| CCM | Cruise Control Module | Cruise Module | Controls and maintains set cruising speed | 2000s | Controls |
| CKP | Crank Position Sensor | Crank Sensor | Detects crankshaft position for ignition timing | 1990s | Engine Sensors |
| DLC | Datalink Connector | Diagnostic Port | Interface for connecting diagnostic tools | 1990s | Diagnostic |
| DTC | Diagnostic Trouble Codes | Trouble Codes | Codes identifying faults in the system | 1990s | Diagnostic |
| ECM | Electronic Control Module | Engine Control Unit (ECU) | Controls engine functions and fuel injection | 1980s-90s | Engine Control |
| ECT | Engine Coolant Temperature | Coolant Temp Sensor | Monitors engine coolant temperature | 1980s | Engine Sensors |
| ECU | Electronic Control Unit | ECU | Central unit controlling engine electronic functions | 1980s-90s | Engine Control |
| EFI | Electronic Fuel Injection | Fuel Injection | Manages precise fuel delivery to the engine | Late 1990s | Fuel System |
| EFP | Electronic Fuel Pump | Fuel Pump | Supplies fuel under pressure to the injectors | 2000s | Fuel System |
| ET | Engine Temperature Sensor | Engine Temp Sensor | Measures engine temperature for monitoring | 1980s | Engine Sensors |
| FI | Fuel Injectors | Injectors | Delivers fuel into engine combustion chambers | Late 1990s | Fuel System |
| FPR | Fuel Pressure Regulator | Fuel Regulator | Maintains consistent fuel pressure | 1980s | Fuel System |
| HCU | Hydraulic Control Unit, ABS | ABS Control Unit | Controls hydraulic pressure for ABS braking | Early 2000s | Braking System |
| H-DSSS | Harley-Davidson Smart Security System | Smart Security System | Provides vehicle anti-theft protection | 2010s | Security |
| HFSM | Hands Free Security Module | Hands Free Module | Enables keyless security and start authorization | 2010s | Security |
| HO2S | Heated Oxygen Sensor | O2 Sensor | Measures oxygen in exhaust to optimize emissions | 1990s | Emission Sensors |
| IAC | Idle Air Control actuator | Idle Control Actuator | Adjusts airflow to maintain engine idle speed | 1990s | Engine Controls |
| IAT | Intake Air Temperature sensor | Intake Temp Sensor | Measures temperature of air entering engine | 1990s | Engine Sensors |
| ICM | Ignition Control Module | Ignition Module | Controls ignition timing for engine firing | 1990s | Engine Control |
| IMAP | MAP + IAT in one unit | Combined MAP/IAT Sensor | Measures intake pressure and air temperature | 2000s | Engine Sensors |
| ISS | Ion Sensing System | Ion Sensor | Detects combustion quality via ion current | 2000s | Engine Sensors |
| JSS | Jiffy Stand Sensor | Kickstand Sensor | Detects kickstand position to prevent riding with it down | 1990s | Safety Controls |
| LHCM | Left Hand Control Module | Left Handlebar Module | Controls left handlebar switches and functions | 2000s | Controls |
| MAP | Manifold Absolute Pressure Sensor | MAP Sensor | Measures pressure in intake manifold | 1990s | Engine Sensors |
| MHR | Right Hand Control Module | Right Handlebar Module | Controls right handlebar switches and functions | 2000s | Controls |
| RCM | Reverse Control Module | Reverse Module | Controls reverse gear engagement and operation | 2010s | Controls |
| TCA | Throttle Control Actuator | Throttle Actuator | Controls throttle valve opening for acceleration | 2000s | Engine Controls |
| TGS | Twist Grip Sensor | Throttle Sensor | Measures throttle grip position | 2000s | Controls |
| TMAP | Intake Air Temperature / MAP sensor | Combined TMAP Sensor | Combines manifold pressure and intake air temp readings | 2000s | Engine Sensors |
| TPS | Throttle Position Sensor | Throttle Sensor | Measures position of throttle for engine control | 1990s | Engine Sensors |
| TSM / TSSM | Turn Signal / Turn Signal Security Module | Turn Signal Module | Controls turn signals and security features | 2000s | Lighting/Security |
| VE | Volume Efficiency | Volume Efficiency Metric | Indicates engine volumetric efficiency (performance) | N/A | Engine Performance |
| VIN | Vehicle Identification Number | VIN | Unique vehicle serial number for identification | Since 1980s | Vehicle Info |
| VSS | Vehicle Speed Sensor | Speed Sensor | Measures vehicle speed for speedometer and controls | 1980s | Vehicle Sensors |
| WSS | Wheel Speed Sensor | Wheel Speed Sensor | Measures wheel rotation speed, used for ABS and controls | 1990s | Vehicle Sensors |
Download the Full Harley Davidson DTC Code Lists
To make your diagnostics easier, we offer downloadable files you can keep on your phone or garage computer:
- 📄 Download the Complete DTC Codes List (PDF): Ideal for printing or offline reading
FAQs
How do I find which DTC my bike has?
Use a scanner or your bike’s built-in diagnostic system to retrieve codes.
Can I reset the codes myself?
Yes, with a scanner or through manual reset if your model supports it.
Do these codes apply to all Harley models?
Most codes follow standard OBD-II protocols, but some vary slightly by model and year.
What do the warning lights on my Harley Davidson dashboard mean?
Warning lights on your dash, like the check engine light, battery symbol, or ABS indicator, are often your first clue that something needs attention. Each light corresponds to a different system and may relate to a specific DTC code. To understand what each light means and what action to take, check out our Harley dash lights meaning guide.
Final Thoughts
Harley Davidson DTC codes are more than just random strings, they’re a powerful insight into your bike’s health. Understanding and using them properly can help you fix issues early, save on repairs, and ride with confidence. Be sure to download our full code list so you’re always prepared, whether you’re at home or on the road.