U0137 code meaning
Lost Communication With Trailer Brake Control Module
What U0137 means
U0137 means the trailer brake control module, which energises a towed trailer’s electric brakes in step with the tow vehicle's braking, is missing on the bus. Ford uses the code widely: on 2022 F-150 trucks without that module the ABS unit may store U0137 by mistake, and it can then be ignored (SSM 50418); on F-150, Expedition, Navigator and Ranger of 2021–2024 the IPC, BCM or PSCM log it together with a warning that the trailer brake module has failed, solved by disconnecting the battery and module and reprogramming the trailer module (SSM 53236). Ram 1500–3500 with integrated trailer brake module can show Park Assist System Disabled with U0137 (FCA 9004253). Invalid data from this module is U0438. Check the trailer brakes before towing.
U0137 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0137
- Trailer brake fault message in the cluster
- Trailer brakes not applied or gain control inoperative
- Park assist disabled on some Ram trucks
Common causes of U0137
- Most likelyTrailer or ABS module software, fixed by reprogramming (Ford SSM 53236, 50418)
- PossibleImproperly seated connector, damaged harness or water intrusion at the module (FCA 9004253)
- PossibleModule retrofitted or configured incorrectly (dealer-installed tow package)
- Less likelyTrailer brake control module internally faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Trailer brake moduleCAN bus wiring
What each part of U0137 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 37 | The exact fault in that area. |
What to do next
- Note U0137 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0137
What does U0137 mean?
U0137 means "Lost Communication With Trailer Brake Control Module". U0137 means the trailer brake control module, which energises a towed trailer’s electric brakes in step with the tow vehicle's braking, is missing on the bus. It is a generic code, so it means the same on every make.
Is it safe to drive with U0137?
U0137 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0137 fail an emissions test?
U0137 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U0137 to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will U0137 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.