Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR DTC U0401-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM
NOTE:
This DTC must be active for the results of this test to be valid.
1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. Cycle the ignition switch from off to on.
4. With the scan tool, read DTCs.
  Does the scan tool display: U0401-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM?
  
  Yes
  - Go To 2.
  No
  - Go To 4.
CHECK IF TIPM CAN BUS DTCS ARE PRESENT
1. With the scan tool, read TIPM DTCs.
  Are there any TIPM CAN BUS DTC's present?
  
  Yes
  - Refer to DIAGNOSIS AND TESTING and perform the appropriate diagnostic procedure.
  No
  - Go To 3.
POWERTRAIN DTCS PRESENT
1. With the scan tool, read PCM DTCs.
  Are there any active DTCs present?
  
  Yes
  - Before continuing with this diagnostic procedure, Refer to DIAGNOSTIC CODE INDEX for 5.7L or DIAGNOSTIC CODE INDEX for 6.7L and perform the appropriate PCM diagnostic procedures.
  No
  - Replace the Drive Train Control Module (DTCM) in accordance with the Service Information.
  - Refer to STANDARD PROCEDURE and perform the DTCM VERIFICATION TEST.
INTERMITTENT WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle test the wiring harness and connectors while checking for shorted and open circuits.
4. Using the scan tool, monitor the data related to this circuit while performing the wiggle test. Look for the data to change or for the DTC to reset.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Refer to STANDARD PROCEDURE and perform TRANSFER CASE VERIFICATION TEST.
  No
  - Test complete.