What Does P1831 Mean?
The transfer case counter-clockwise shift relay control circuit is shorted to ground. This causes unintended relay activation or prevents the control module from properly commanding the shift motor.
Common Causes
40%
Chafed or pinched wiring harness grounding the control circuit
25%
Failed transfer case shift relay with internal short to ground
20%
Damaged or corroded relay socket causing ground short
15%
Transfer case control module internal failure with shorted output driver
Diagnostic Steps
1
Step 1: Disconnect the transfer case shift relay and measure resistance from the control coil terminal to ground (should be high resistance/open)
2
Step 2: Inspect wiring harness routing for pinch points, especially near frame rails, exhaust, or sharp edges
3
Step 3: Check for moisture or corrosion in the relay socket and connector terminals
4
Step 4: Perform a resistance test on the relay coil itself to verify it's not internally shorted
5
Step 5: Disconnect the control module connector and retest the circuit to isolate module vs. wiring fault
Estimated Repair Cost
$150 - $800
Parts + labor, varies by vehicle and location
The transfer case counter-clockwise shift relay control circuit is shorted to ground. This causes unintended relay activation or prevents the control module from properly commanding the shift motor.
The most common cause of P1831 (Transmission Transfer Case Counter Clockwise Shift Relay Coil Short Circuit To Ground) is: Chafed or pinched wiring harness grounding the control circuit
Typical repair costs for P1831 range from $150 to $800, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Transfer case may not shift properly between drive modes, potentially causing unexpected drivetrain behavior or inability to engage/disengage four-wheel drive. Avoid off-road use until repaired.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1831 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Transfer Case / Four-Wheel Drive System
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
