Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Jeep Compass TrailhawkFACTORY OEM SERVICE PROCEDURE
Module, Trailer Tow
DIAGNOSTIC CODE INDEX
| DTC | Description |
|---|---|
| B166A-11 | LEFT TRAILER TOW LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B166A-12 | LEFT TRAILER TOW LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B166A-13 | LEFT TRAILER TOW LAMP CONTROL - CIRCUIT OPEN |
| B166E-11 | RIGHT TRAILER TOW LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B166E-12 | RIGHT TRAILER TOW LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B166E-13 | RIGHT TRAILER TOW LAMP CONTROL - CIRCUIT OPEN |
| B16BB-11 | TRAILER STOP LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B16BB-12 | TRAILER STOP LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B16BB-13 | TRAILER STOP LAMP CONTROL - CIRCUIT OPEN |
| B17AD-11 | REAR LEFT TRAILER TURN LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B17AD-12 | REAR LEFT TRAILER TURN LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B17AD-13 | REAR LEFT TRAILER TURN LAMP CONTROL - CIRCUIT OPEN |
| B17B1-11 | REAR RIGHT TRAILER TURN LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B17B1-12 | REAR RIGHT TRAILER TURN LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B17B1-13 | REAR RIGHT TRAILER TURN LAMP CONTROL - CIRCUIT OPEN |
| B17C5-11 | TRAILER TOW REVERSE LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B17C5-12 | TRAILER TOW REVERSE LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B17C5-13 | TRAILER TOW REVERSE LAMP CONTROL - CIRCUIT OPEN |
| B17C9-11 | TRAILER TOW REAR FOG LAMP CONTROL - CIRCUIT SHORT TO GROUND |
| B17C9-12 | TRAILER TOW REAR FOG LAMP CONTROL - CIRCUIT SHORT TO BATTERY |
| B17C9-13 | TRAILER TOW REAR FOG LAMP CONTROL - CIRCUIT OPEN |
| B22A9-00 | ECU INTERNAL PERFORMANCE |
| B235C-64 | TRAILER CONNECTION - SIGNAL PLAUSIBILITY FAILURE |
| C10CB-8F | VEHICLE SPEED OUTPUT - ERRATIC |
| U0010-00 | CAN INTERIOR BUS |
| U0011-00 | CAN INTERIOR BUS OFF PERFORMANCE |
| U0140-00 | LOST COMMUNICATION WITH BODY CONTROL MODULE |
| U0155-00 | LOST COMMUNICATION WITH CLUSTER-CCN |
| U0422-00 | IMPLAUSIBLE DATA RECEIVED FROM BODY CONTROL MODULE |
| U0423-00 | IMPLAUSIBLE DATA RECEIVED FROM CLUSTER-CCN |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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