What Does U0137 Mean?
The vehicle's communication network has lost contact with the Trailer Brake Control Module. This module manages electric trailer brake application in coordination with the vehicle's braking system.
Safety Warning
Electric trailer brakes will not function when towing, significantly increasing stopping distance and creating dangerous driving conditions. Do not tow until repaired.
Common Causes
30%
Trailer Brake Control Module internal failure or relay malfunction
30%
Corroded or damaged connector at module due to weather exposure
20%
Wiring harness damage in trailer tow package circuit
15%
Power supply circuit fault or blown trailer brake fuse
5%
CAN bus circuit interruption or termination fault
Diagnostic Steps
1
Step 1: Check trailer brake controller fuse and power supply voltage at module
2
Step 2: Inspect trailer brake controller connector for corrosion, especially if mounted in exposed location
3
Step 3: Verify ground circuit integrity and test for excessive resistance
4
Step 4: Test CAN bus communication signals at module connector for proper voltage levels
5
Step 5: Disconnect trailer connector and retest to rule out trailer-side circuit faults
Estimated Repair Cost
$150 - $800
Parts + labor, varies by vehicle and location
The vehicle's communication network has lost contact with the Trailer Brake Control Module. This module manages electric trailer brake application in coordination with the vehicle's braking system.
The most common cause of U0137 (Lost Communication With Trailer Brake Control Module) is: Trailer Brake Control Module internal failure or relay malfunction
Typical repair costs for U0137 range from $150 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Electric trailer brakes will not function when towing, significantly increasing stopping distance and creating dangerous driving conditions. Do not tow until repaired.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to U0137 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Network
System
Trailer Brake Control System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
