What does it mean?
C1400 is a Chassis (ABS, traction control, steering) fault code. It indicates: Transfer Case Range Select Switch Performance . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms
- Four wheel drive warning lamp or a service message for the drivetrain
- Range selection does not change, or only works occasionally
- Selector indicator lamps flash or show more than one range lit
- Vehicle stuck in whichever range it was in when the fault appeared
- Low range cannot be engaged
Likely causes
- Worn or dirty contacts inside the transfer case range select switch
- Failing switch signalling two range positions at once
- Corroded or loose connector at the switch or at the transfer case control module
- Chafed wiring in the switch harness behind the console or under the dash
- Switch damaged or knocked out of position during console or trim work
- Low voltage or a poor ground at the transfer case control module
- Control module input fault
How to fix it
- Watch the switch state in live data while cycling slowly through every position
- Inspect the switch connector for corrosion, bent pins and loose terminals
- Bench test or measure the switch for the correct continuity pattern in each position
- Check the switch supply voltage and ground at the connector
- Inspect the harness where it passes bulkheads, brackets and moving trim
- Confirm that the shift conditions such as vehicle speed, neutral and brake input are being met before condemning parts
- Replace the range select switch, then recheck the shift motor and encoder if the fault remains