As the name suggests, a fault code (a.k.a. Diagnostic Trouble Code (DTC)) indicates that the self-diagnostic system of your Harley-Davidson has detected a malfunction. These codes are accompanied by a solid security light (red light) that stays on after the bike has been started.
If you want to find out more about the topic and browse through the official Harley-Davidson fault codes in one chart, this post is for you.
We at PowerSportsGuide have compiled all you need to know under one roof!
All About Harley-Davidson Fault (DTC) Codes
What is the Check Engine Light for on a Harley-Davidson?
A solid check engine light on your Harley-Davidson’s dashboard indicates that the diagnostic system has detected a malfunction. If this indicator light solidly stays on after the ignition is turned on, it’s a sign that a fault code is present.
If your Harley is in perfect condition, this light should disappear when you start the bike.
But if it stays on, it tells you that a current DTC is present, meaning that your bike has a malfunction.
Are you wondering what DTC codes are on a Harley?
Keep reading!
What Does DTC Mean on a Harley?
Simply put, DTC is an abbreviation that stands for “Diagnostic Trouble Codes”. As the name suggests, DTC codes indicate the presence of a problem on a Harley, and each one corresponds to a specific malfunction.
An issue can be indicated by one or multiple fault codes depending on the nature of the problem. DTC codes are often referred to as error codes, flashing codes, or just diagnostic codes.
They can be classed into three different categories:
- Current: Current (or active) DTC codes indicate that the diagnostic system detects an active malfunction, and the bike should be inspected immediately. These codes can only be cleared after the malfunction has been eliminated.
- Historic: Historic DTC codes remain saved in the memory until 40 ignition cycles have occurred or until they are cleared manually.
- Pending: Pending DTC codes indicate malfunctions that haven’t been a problem long enough to become a current code. In other words, if the malfunction resolves itself, a pending DTC code will turn into an historic code without becoming a current code.
Let’s get down to the nitty-gritty and talk about how to read Harley-Davidson trouble codes!
How do You Check the DTC Codes on a Harley-Davidson?
You can read the DTC codes on a Harley-Davidson without a diagnostic tool by using the trip reset button. The main steps in this process are as follows:
- Make sure that your battery is charged and its terminals are secured.
- Turn the Run/Stop switch to the Run position.
- Push and hold down the trip reset button (a.k.a. odometer reset button).
- Turn the ignition switch to Ignition.
- Release the trip reset button.
- At this point, background and indicator lights should illuminate and the needles should sweep across the speedo and tachometers.
- You will also read a “DIAG” message on the dash, indicating that you are in diagnostic mode.
- Push the trip reset button to go through the different modules. Each letter/abbreviation represents an area of a different diagnostics module. The module that is flashing needs a closer look.
- You can display the DTC code by holding down the trip reset button for five seconds.
- If DTC codes are displayed, record them for later use. If there aren’t any codes on that module, you will read a “none” message on the dash.
- Turn Ignition to OFF.
Where is the trip reset button on a Harley Davidson?
On older models, it’s typically mounted behind the speedometer while later bikes have it on the left handlebar.
How do You Clear the DTC Code on a Harley-Davidson?
You can delete a DTC code on your Harley-Davidson by pressing the odometer reset button. Just navigate to the fault code in the menu as described above, then press and hold the reset button for about five seconds until the message “CLEAR” appears.
As the final step, release the reset button and turn the ignition switch off.
If your bike displays more than one fault code, repeat these steps through the other codes.
Once you’ve cleared the DTCs, don’t skip the road test to make sure that the codes don’t make a comeback. A quick ride is very important since some codes only appear if the bike reaches a certain speed or due to other inputs caused during the ride.
After your ride, you may want to enter the menu again and check the codes to see if they are gone.
NOTE: Once they have cleared, historic DTC codes won’t reappear after the test ride procedure. In contrast, current fault codes can make a comeback after this process, which tells you that your bike requires further inspection and repair.
What Are the Different Types of Harley-Davidson Fault Codes?
The DTC codes on Harley-Davidsons are alphanumeric codes containing a letter followed by four digits. On newer models the four types (modules) of DTC codes are labeled with abbreviations, which are as follows:
- ECM: Electronic Control Module
- BCM: Body Control Module
- SPDO: Speedometer
- RAD: Radio
In contrast, on older Harley-Davidsons the fault code categories are described with letters:
- P Codes: ECM
- C Codes: ABS
- B Codes: Radio, Instruments, BCM
- U Codes: Module communication
These categories are known as “modules” in the onboard diagnostic system.
Harley-Davidson DTC Lists [Fault Code Charts]
For your convenience, we’ve listed the official fault codes and their meanings in these Harley-Davidson DTC charts:
Harley-Davidson P Codes [ECM]
| P0031 | Front HO2S low/open |
| P0032 | Front HO2S shorted/high |
| P0051 | Rear HO2S low/open |
| P0052 | Rear HO2S shorted/high |
| P0072 | AAT sensor low |
| P0073 | AAT sensor high/open |
| P0107 | MAP sensor failed low/open |
| P0107 | Map Sensor Open/Low |
| P0108 | MAP sensor failed high/open port |
| P0112 | IAT Voltage Low |
| P0113 | IAT Voltage Open/High |
| P0117 | ET Sensor Low |
| P0118 | ET Sensor High |
| P0120 | TPS1 Range Error |
| P0122 | TPS1 Low |
| P0123 | TPS2 High/Open |
| P0131 | Front Oxygen Sensor Low / Engine Lean |
| P0132 | Front Oxygen Sensor High / Engine Rich |
| P0134 | Front Oxygen Sensor Inactive |
| P0151 | Rear Oxygen Sensor Low / Engine Lean |
| P0152 | Rear Oxygen Sensor High / Engine Rich |
| P0154 | Rear Oxygen Sensor Inactive |
| P0220 | TPS2 Range Error |
| P0222 | TPS2 Low/Open |
| P0223 | TPS2 High/Open |
| P0261 | Front Injector Open/Low |
| P0262 | Front Injector High |
| P0263 | Rear Injector Open/Low |
| P0264 | Rear Injector High |
| P0265 | Rear injector shorted high |
| P0371 | CKP sensor wrong number of pulses |
| P0373 | CKP Sensor Intermittent |
| P0374 | CKP Sensor Synch Error |
| P0444 | Purge Solenoid Open/Low |
| P0445 | Purge Solenoid High |
| P0501 | VSS Sensor Low |
| P0502 | VSS Sensor High/Open |
| P0503 | VSS failed high |
| P0505 | Idle speed control unstable |
| P0562 | Battery/ECM Voltage Low |
| P0563 | Battery/ECM Voltage High |
| P0572 | Brake Switch Low |
| P0577 | Cruise Control Input High |
| P0603 | ECM EEPROM Memory Error |
| P0605 | ECM FLASH Memory Error |
| P0641 | 5 Volt Reference 1 Out of Range |
| P0651 | 5 Volt Reference 2 Out of Range |
| P0691 | Fan/cooling relay output low/open |
| P0692 | Fan/cooling relay output high |
| P1001 | System Relay Coil Open/Low |
| P1002 | System Relay Coil High/Shorted |
| P1003 | System Relay Contacts Open |
| P1004 | System Relay Contacts Closed |
| P1009 | VTD Disabled Fuel Due to Incorrect Password |
| P1010 | Missing Password |
| P1017 | ET Indicates Overheating |
| P1019 | ECT Difference (high temp) |
| P1270 | TGS 2 A/D Validation Error |
| P1351 | Front Ignition Coil Driver Open/Low |
| P1352 | Front Ignition Coil Driver High/Shorted |
| P1353 | Front Cylinder No Combustion |
| P1354 | Rear Ignition Coil Driver Open/Low |
| P1355 | Rear Ignition Coil Driver High/Shorted |
| P1356 | Rear Cylinder No Combustion |
| P1357 | Front Cylinder Combustion Intermittent |
| P1358 | Rear Cylinder Combustion Intermittent |
| P1475 | Exhaust Actuation Position Error |
| P1477 | Exhaust Actuator Open/Low |
| P1478 | Exhaust Actuator Shorted/High |
| P1501 | Jiffy Stand Sensor Low |
| P1502 | Jiffy Stand Sensor High |
| P1510 | EFI Limited Performance Mode |
| P1511 | EFI Power Management Mode |
| P1512 | EFI Forced Idle Mode |
| P1514 | ETC Air Flow Fault/Error |
| P1600 | EFI Module Processor Internal Error / Watchdog Error |
| P1608 | Loss of Continuous Battery |
| P1655 | ACR Solenoid Low/Open |
| P1656 | ACR Solenoid Shorted High |
| P1691 | Cooling Fan Left Low/Open |
| P1692 | Cooling Fan Left Shorted High |
| P1693 | Cooling Fan Right Low/Open |
| P1694 | Cooling Fan Right Shorted High |
| P2100 | EFI Motor Circuit Open |
| P2101 | EFI Motor Circuit Range Performance (Actuation Error) |
| P2102 | EFI Motor Circuit Low |
| P2103 | EFI Motor Circuit High |
| P2105 | EFI Forced Engine Shutdown |
| P2107 | EFI Module Processor Internal Fault |
| P2119 | EFI Motor Throttle Body Range Performance |
| P2122 | TGS1 Low/Open |
| P2123 | TGS1 High |
| P2127 | TGS2 Low/Open |
| P2128 | TGS2 High |
| P2135 | TPS Correlation Error |
| P2138 | TGS Correlation Error (Twist grip sensor) |
| P2176 | EFI Closed Position Not Learned |
| P2184 | ECT Sensor Low |
| P2185 | ECT Sensor High |
| P2300 | Ignition Coil Driver Low/Open (front) |
| P2301 | Ignition Coil Driver Shorted High (front) |
| P2303 | Ignition Coil Driver Low/Open (rear) |
| P2304 | Ignition Coil Driver Shorted High (rear) |
Harley-Davidson C Codes: [ABS]
| C0562 | ABS Voltage Low |
| C0563 | ABS Voltage High |
| C1014 | ABS ECU Relay Error |
| C1021 | ABS Front WSS Always Zero |
| C1023 | ABS Rear WSS Always Zero |
| C1025 | ABS Front Wheel Speed Intermittent |
| C1027 | ABS Rear Wheel Speed Intermittent |
| C1029 | ABS Wheel Speed Difference Too High |
| C1032 | ABS Front Wheel Speed Circuit Open/Shorted |
| C1034 | ABS Rear Wheel Speed Circuit Open/Shorted |
| C1040 | ABS Pump/Motor Error |
| C1055 | ABS ECU Internal Error |
| C1061 | ABS Front Apply Solenoid Circuit Open/High Resistance |
| C1062 | ABS Front Release Solenoid Circuit Open/High Resistance |
| C1065 | ABS Rear Apply Solenoid Circuit Open/High Resistance |
| C1066 | ABS Rear Release Solenoid Circuit Open/High Resistance |
| C1071 | Rear Prime Valve Error |
| C1072 | Rear Isolation Valve Error |
| C1073 | Front Isolation Valve Error |
| C1074 | Front Prime Valve Error |
| C1075 | Front Linked Inlet Valve Error |
| C1076 | Front Linked Outlet Valve Error |
| C1077 | Front Circuit Pressure Sensor Error |
| C1078 | Rear Circuit Pressure Sensor Error |
| C1081 | Front Master Pressure Sensor Error |
| C1082 | Front Master Pressure Sensor Offset Error |
| C1083 | Front Wheel Pressure Sensor Error |
| C1084 | Front Wheel Pressure Sensor Offset Error |
| C1085 | Rear Master Pressure Sensor Error |
| C1086 | Rear Master Pressure Offset Sensor Error |
| C1087 | Rear Wheel Pressure Sensor Error |
| C1088 | Rear Wheel Pressure Sensor Offset Error |
| C1089 | Pressure Sensor External Supply Error |
| C1159 | ABS Invalid Stored VIN |
| C1178 | ABS No VIN Received From ECM |
| C1184 | ABS Invalid VIN From ECM |
| C1195 | Wake Up Error |
Harley-Davidson B Codes: [Radio, Instruments, BCM]
| B0563 | Battery Voltage High |
| B1103 | LHCM Internal Error |
| B1121 | (HFSM) Left Turn Output Open |
| B1121 | (TSM) Left Turn Output Fault |
| B1122 | (HFSM) Right Turn Output Open |
| B1122 | (TSM) Right Turn Output Fault |
| B1123 | (HFSM) Left Turn Output Short to Ground |
| B1124 | (HFSM) Right Turn Output Short to Ground |
| B1125 | (HFSM) Left Turn Output Short to Battery |
| B1126 | (HFSM) Right Turn Output Short to Battery |
| B1131 | (HFSM) Alarm Output Low |
| B1132 | (HFSM) Alarm Output High |
| B1134 | Starter Output High |
| B1135 | Accelerometer Failed |
| B1136 | (HFSM) Accelerometer Tip Test Error |
| B1141 | (HFSM) Ignition Switch Low/Open |
| B1141 | (TSM) Ignition Switch Low/Open |
| B1142 | Smart Security System Internal Fault |
| B1143 | (HFSM) Security Antenna Short to Ground |
| B1144 | (HFSM) Security Antenna Short to Battery |
| B1145 | (HFSM) Security Antenna Open |
| B1151 | Bank Angle Sensor (BAS) Short to Ground |
| B1152 | Bank Angle Sensor (BAS) Short to Battery |
| B1153 | Bank Angle Sensor (BAS) High |
| B1153 | RHCM Internal Error |
| B1154 | Clutch Switch Input Short to Ground |
| B1155 | Neutral Switch Input Short to Battery |
| B1200 | IM Internal Fault |
| B1210 | Fuel level Sender Shorted Low/Open |
| B1211 | Fuel level Sender Shorted High |
| B1212 | Fuel signal Low |
| B1213 | Fuel Signal High |
| B1300 | Radio Voltage High |
| B1301 | Radio Voltage Low |
| B1302 | Face Plate Home Button Stuck |
| B1303 | Face Plate Favorite Button Stuck |
| B1304 | Face Plate Navigation Button Stuck |
| B1305 | Face Plate Power/Mute Button Stuck |
| B1306 | Rear Hand Controls Shorted High |
| B1307 | Rear Hand Controls Shorted Low |
| B1308 | Rear Volume Up Button Stuck |
| B1309 | Rear Volume Down Button Stuck |
| B1310 | Rear Mode Button Stuck |
| B1311 | Rear PTT Button Stuck |
| B1312 | Rear Tune Up Button Stuck |
| B1313 | Rear Tune Down Button Stuck |
| B1314 | LHCM VR Button Stuck |
| B1315 | LHCM Up Button Stuck |
| B1316 | LHCM Left Button Stuck |
| B1317 | LHCM Center Button Stuck |
| B1318 | LHCM Right Button Stuck |
| B1319 | LHCM Down Button Stuck |
| B1320 | RHCM Info Button Stuck |
| B1321 | RHCM Up Button Stuck |
| B1322 | RHCM Left Button Stuck |
| B1323 | RHCM Center Button Stuck |
| B1324 | RHCM Right Button Stuck |
| B1325 | RHCM Down Button Stuck |
| B1326 | RHCM CB Squelch Up Button Stuck |
| B1327 | RHCM CB PTT Button Stuck |
| B1328 | RHCM CB Squelch Down Button Stuck |
| B1329 | Faceplate Preset Button 1 Stuck |
| B1330 | Faceplate Preset Button 2 Stuck |
| B1331 | Faceplate Preset Button 3 Stuck |
| B1332 | Faceplate Preset Button 4 Stuck |
| B1333 | Faceplate Preset Button 5 Stuck |
| B1334 | Faceplate Preset Button 6 Stuck |
| B1335 | Faceplate Preset Button 7 Stuck |
| B1336 | Faceplate Preset Button 8 Stuck |
| B1337 | Front Left Speaker Shorted Together |
| B1338 | Front Left Speaker Open |
| B1339 | Front Left Speaker Shorted Low |
| B1340 | Front Left Speaker Shorted High |
| B1341 | Rear Left Speaker Shorted Together |
| B1342 | Rear Left Speaker Open |
| B1343 | Rear Left Speaker Shorted Low |
| B1344 | Rear Left Speaker Shorted High |
| B1345 | Front Right Speaker Shorted Together |
| B1346 | Front Right Speaker Open |
| B1347 | Front Right Speaker Shorted Low |
| B1348 | Font Right Speaker Shorted High |
| B1349 | Rear Right Speaker Shorted Together |
| B1350 | Rear Right Speaker Open |
| B1351 | Rear Right Speaker Shorted Low |
| B1352 | Rear Right Speaker Shorted High |
| B1353 | Speaker Offset DC Output |
| B1354 | GPS Antenna Open |
| B1355 | GPS Antenna Shorted Low |
| B1356 | SDARS Antenna Open |
| B1357 | SDARS Antenna Shorted |
| B1358 | Front Left Headset Shorted High |
| B1359 | Front Right Headset Shorted High |
| B1360 | Front Left Headset Shorted Low |
| B1361 | Front Right Headset Shorted Low |
| B1362 | Rear Left Headset Shorted High |
| B1363 | Rear Right Headset Shorted High |
| B1364 | Rear left headset shorted low |
| B1365 | Rear Right Headset Shorted Low |
| B1366 | Internal Thermal Shutdown Error |
| B1401 | Amp Voltage Low |
| B1402 | Amp Voltage High |
| B1403 | Speaker Offset DC Output |
| B1404 | Internal Thermal Shutdown Error |
| B1405 | EQ Correlation Error |
| B1406 | Invalid or Missing EQ |
| B1410 | Channel 1 Speaker Open |
| B1411 | Channel 1 Speaker Shorted Low |
| B1412 | Channel 1 Speaker Shorted High |
| B1413 | Channel 1 Speaker Shorted Together |
| B1420 | Channel 2 Speaker Open |
| B1421 | Channel 2 Speaker Shorted Low |
| B1422 | Channel 2 Speaker Shorted High |
| B1423 | Channel 2 Speaker Shorted Together |
| B1430 | Channel 3 Speaker Open |
| B1431 | Channel 3 Speaker Shorted Low |
| B1432 | Channel 3 Speaker Shorted High |
| B1433 | Channel 3 Speaker Shorted Together |
| B1440 | Channel 4 Speaker Open |
| B1441 | Channel 4 Speaker Shorted Low |
| B1442 | Channel 4 Speaker Shorted High |
| B1443 | Channel 4 Speaker Shorted Together |
| B2102 | System Power Output Shorted High |
| B2103 | System Power Output Shorted Low |
| B2104 | System Power Output Overloaded |
| B2106 | L4 Output Open |
| B2107 | L4 Output Shorted High |
| B2108 | L4 Output Shorted Low |
| B2109 | L4 Output Overloaded |
| B2112 | ACC Output Shorted High |
| B2113 | ACC Output Shorted Low |
| B2114 | ACC Output Overloaded |
| B2116 | Fuel Pump Output Open |
| B2117 | Fuel Pump Output Shorted High |
| B2118 | Fuel Pump Output Shorted Low |
| B2119 | Fuel Pump Output Overloaded |
| B2121 | Starter Output Open |
| B2122 | Starter Output Shorted High |
| B2123 | Starter Output Shorted Low |
| B2124 | Starter Output Overloaded |
| B2127 | E4 Output Shorted High |
| B2128 | E4 Output Shorted Low |
| B2129 | E4 Output Overloaded |
| B2131 | High Beam Output Open |
| B2132 | High Beam Output Shorted High |
| B2133 | High Beam Output Shorted Low |
| B2134 | High Beam Output Overloaded |
| B2136 | Low Beam Output Open |
| B2137 | Low Beam Output Shorted High |
| B2138 | Low Beam Output Shorted Low |
| B2139 | Low Beam Output Overloaded |
| B2141 | Left Front Turn Signal output Open |
| B2143 | Left Front Turn Signal Output Shorted Low |
| B2144 | Left Front Turn Signal Output Overloaded |
| B2146 | Right Front Turn Signal Output Open |
| B2148 | Right Front Turn Signal Output Shorted Low |
| B2149 | Right Front Turn Signal Output Overloaded |
| B2151 | Left Rear Turn Signal Output Open |
| B2153 | Left Rear Turn Signal Output Shorted Low |
| B2154 | Left Rear Turn Signal Output Overloaded |
| B2156 | Right Rear Turn Signal Output Open |
| B2158 | Right Rear Turn Signal Output Shorted Low |
| B2159 | Right Rear Turn Signal Output Overloaded |
| B2161 | Brake Lamp Output Open |
| B2163 | Brake Lamp Output Shorted Low |
| B2164 | Brake Lamp Output Overloaded |
| B2168 | Running Lights Output Shorted Low |
| B2169 | Running Lights Output Overloaded |
| B2172 | H2 Output Shorted High |
| B2173 | H2 Output Shorted Low |
| B2176 | Security Antenna Output Open |
| B2177 | Security Antenna Output Shorted High |
| B2178 | Security Antenna Output Shorted Low |
| B2183 | G2 Output Shorted Low |
| B2188 | G3 Output Shorted Low |
| B2193 | H4 Output Shorted Low |
| B2198 | H3 Output Shorted Low |
| B2201 | IGN Switch Off w/VSS |
| B2203 | Ignition Switch Input Shorted Low |
| B2206 | Run/Stop Switch Input Open/Shorted High |
| B2208 | Run/Stop Switch Input Shorted Low |
| B2210 | Run/Stop Switch Inputs Both Open |
| B2212 | Run/Stop Switch Inputs Both Closed |
| B2218 | Neutral Switch Shorted Low |
| B2223 | Rear Brake Switch Shorted Low (light on) |
| B2226 | BAS Input Open |
| B2228 | BAS Input Shorted Low |
| B2231 | Fork Locked/VSS |
| B2232 | Fork Lock Shorted High |
| B2233 | Fork Lock Shorted Low |
| B2234 | Fork Lock Detected With Option Disabled |
| B2235 | Fork Lock Configuration Invalid |
| B2250 | Clutch Switch Stuck |
| B2251 | Horn Switch Stuck |
| B2253 | FTP Switch Stuck |
| B2254 | Left Turn Switch Stuck |
| B2255 | Trip Switch Stuck |
| B2256 | LHCM Police Siren Power Stuck |
| B2257 | LHCM Police Siren Wail Power Stuck |
| B2258 | LHCM Police Siren Yelp Stuck |
| B2260 | Start Switch Stuck |
| B2261 | Right Turn Switch Stuck |
| B2262 | Front Brake Switch Stuck |
| B2263 | Hazard Switch Stuck |
| B2264 | RHCM Police Lights Power Switch Stuck |
| B2265 | RHCM Police Lights Front Switch Stuck |
| B2266 | RHCM Police Lights Rear Switch Stuck |
| B2267 | RHCM Police ICR Switch Stuck |
| B2270 | BCM Internal Error |
| B2271 | BCM Voltage Low |
| B2272 | BCM/IM Voltage High |
| B2274 | Constant Battery Line Error |
Harley-Davidson U Codes: [Module Communication]
| U0001 | CAN BUS Error |
| U0002 | CAN BUS Perf Error |
| U0003 | Network Management Monitoring |
| U0100 | Lost Comm w/ECM |
| U0121 | Lost Comm W/ABS |
| U0140 | Lost Comm W/BCM |
| U0141 | Lost Comm w/LHCM |
| U0142 | Lost Comm w/RHCM |
| U0156 | Lost Comm w/SPEEDO |
| U0158 | Lost Comm w/Fuel Gauge |
| U0159 | Lost Comm w/Volt Gauge |
| U0160 | Lost Comm w/ Fuel and Volt Gauge |
| U0184 | Lost Comm w/Radio |
| U0185 | Lost Comm w/Amp 1 |
| U0186 | Lost Comm w/ AMP 2 |
| U1016 | Loss of ECM Serial Data |
| U1064 | Loss of TSM/FSFM Serial Data to ECM |
| U1097 | Loss of SpeedometerSerial Data to ECM |
| U1255 | Serial Data Error |
| U1300 | ECM Serial Data Low |
| U1300 | Serial Data Low |
| U1301 | ECM Serial Data High |
| U1301 | Serial Data High |
| U1302 | ACC Bus Perf Error |
| U1401 | Lost com w/CB |
Disclaimer: These charts are for informational purposes only! Please note that these codes may not necessarily apply to every model since the exact codes may vary depending on the year and model. For more information, please check your bike’s service manual!
Harley-Davidson Fault Code Abbreviations
If you take a closer look at the charts above, you can see that the manufacturer uses many abbreviations to describe its DTC codes.
For a better understanding, we’ve listed the meanings of these abbreviations below:
- ABS: Anti-Lock Braking System
- ACR: Automatic Compression Release
- AFR: Air Fuel Ratio
- AIS: Active Intake Solenoid
- ATS: Air Temperature Sensor
- BAS: Bank Angle Sensor
- BCM: Body Control Module
- CAN: Controller Area Network
- CCM: Cruise Control Module
- CKP: Crank Position Sensor
- DLC: Datalink Connector
- DTC: Diagnostic Trouble Codes
- ECM: Electronic Control Module
- ECT: Engine Coolant Temperature
- ECU: Electronic Control Unit
- EFI: Electronic Fuel Injection
- EFP: Electronic Fuel Pump
- ET: Engine Temperature sensor
- FI: Fuel Injectors
- FPR: Fuel Pressure Regulator
- H-DSSS: Harley-Davidson® Smart Security System
- HCU: Hydraulic Control Unit, ABS
- HFSM: Hands Free Security Module
- HO2S: Heated Oxygen Sensor
- IAC: Idle Air Control actuator
- IAT: Intake Air Temperature sensor
- ICM: Ignition Control Module
- IMAP: MAP + IAT in one unit
- ISS: Ion Sensing System
- JSS: Jiffy Stand Sensor
- LHCM: Left Hand Control Module
- MAP: Manifold Absolute Pressure sensor
- MHR: Right Hand Control Module
- RCM: Reverse Control Module
- TCA: Throttle Control Actuator
- TGS: Twist Grip Sensor
- TMAP: Intake Air Temperature / Manifold Absolute Pressure equipment
- TPS: Throttle Position Sensor
- TSM / TSSM: (Turn Signal / Turn Signal Security Module)
- VE: Volume Efficiency
- VIN: Vehicle Identification Number
- VSS: Vehicle Speed Sensor
- WSS: Wheel Speed Sensor
What is the Red Light on a Harley-Davidson for?
A solid red light on a Harley-Davidson’s speedometer is an indication of a faulty light bulb. If this red light stays solidly on after the ignition is turned on, it’s a sign that you should check the lights on your bike.
Conclusion
DTC (Diagnostic Trouble Codes) are the fault or error codes on Harley-Davidsons. They are intended to describe specific malfunctions detected by the bike’s onboard diagnostic system.
DTC codes often indicate a minor malfunction like a loosened battery terminal or a faulty sensor, but they can also indicate serious malfunctions.
The presence of fault codes is always accompanied by an illuminated “check engine light” on the dashboard.
You can read, browse, and clear the fault codes on a Harley-Davidson with the odometer reset button.
The detailed DTC code list accompanied by the list of the related abbreviations in our post can be a great start to diagnosing and fixing your bike. You can also find a more detailed description of the issue and its remedy in your bike’s service manual.
Although error codes can be deleted by the press of a button, it’s highly recommended that you don’t clear them until the malfunction(s) has been repaired.
If you are not mechanically inclined, best practice is to take your bike to a professional for further assistance!
Disclaimer: This post is for informational purposes only! For a more precise diagnosis and service recommendation, please always refer to your bike’s service manual, or get it inspected by a professional.
Sources:
https://www.uti.edu/blog/motorcycle/trouble-codes
https://www.wilkinsharley.com/–Checking-Trouble-Codes-2019-Harley-Davidsons
https://www.appletonhd.com/harley-davidson-trouble-codes/
