Diagnostic Test

WARNING: This page is about a different car, the 2016 Jeep Wrangler and 2015 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY DIAGNOSTIC TROUBLE CODE (DTC) IS ACTIVE

NOTE:

Make sure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.

Turn the ignition on.
With the scan tool, read ORC DTCs.
Is the U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE SYSTEM (ABS) CONTROL MODULE DTC active?

Yes
- Refer to DIAGNOSIS AND TESTING and perform the U0121-Lost Communication with Anti-lock Brake System (ABS) Control Module diagnostic procedure.
No
- Refer to STORED LOST COMMUNICATION DTCS and perform the Stored Lost Communication DTCs diagnostic procedure.