Circuit/System Testing
WARNING: This page is about a different variant/trim than selected.
- Observe the 4WD Signal in the ECM Data List. The 4WD signal should display Enabled when you shift into 4WD and Disabled when you shift into 2WD or neutral.
- If the scan tool display does not match the transfer case range switch state, repair the transfer case system. Refer to Diagnostic System Check - Vehicle .
- If the scan tool matches the transfer case range switch state, continue with testing.
- Program the ECM with the latest software version and retest for DTCs.
- If the DTC resets, replace the ECM.