Diagnostic Test
WARNING: This page is about a different car, the 2012 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR DTCS U0001-CAN C BUS DTC or U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE MODULE
- With the scan tool, check DTCs.
Is DTC U0001-CAN C BUS DTC or U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE MODULE set?
Yes
- Refer to DIAGNOSIS AND TESTING and perform the diagnostic procedure for U0001-CAN C BUS DTC first if it is present.
- Refer to STANDARD PROCEDURE and perform the NAG1 TRANSMISSION VERIFICATION TEST.
No
- Go To 2.
- With the scan tool, check DTCs.
- CHECK FOR ABS DTCS
- With the scan tool, read ABS DTCs.
Are there any ABS DTCs present?
Yes
- Refer to DIAGNOSIS AND TESTING and perform the appropriate diagnostic procedure.
- Refer to STANDARD PROCEDURE and perform the NAG1 TRANSMISSION VERIFICATION TEST.
No
- Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the TCM in accordance with the Service Information.
- Refer to STANDARD PROCEDURE and perform the NAG1 TRANSMISSION VERIFICATION TEST.
- With the scan tool, read ABS DTCs.