Diagnostic Test

TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, record and erase the DTCs.
3. Cycle the ignition from on to off 3 times.
4. Turn the ignition on.
5. With the scan tool, read the DTCs.
  Does the scan tool display: U0020-CAN B BUS OFF PERFORMANCE?
  
  Yes
  - Go to step 2
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the SYSTEM WIRING DIAGRAMS as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and poor pin fit.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure .
CHECK TOTALLY INTEGRATED POWER MODULE DTCs
1. With the scan tool, read the Totally Integrated Power Module DTCs.
  Does the scan tool display any CAN B BUS DTCs - ACTIVE?
  
  Yes
  - Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Diagnosis and Testing and perform the appropriate diagnostic procedure.
  No
  - Go to step 3
CAN B BUS (+) CIRCUIT OPEN

Fig 1: Checking CAN B BUS (+) Circuit Open
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the Amplifier C1 harness connector.
3. Disconnect the Totally Integrated Power Module C3 harness connector.
4. Measure the resistance of the (D55) CAN B BUS (+) circuit between the Totally Integrated Power module C3 harness connector and the Amplifier C1 harness connector.
  Is the resistance below 2.0 Ohms?
  
  Yes
  - Go to step 4
  No
  - Repair the CAN B BUS (+) circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure .
CAN B BUS (-) CIRCUIT OPEN

Fig 2: Checking CAN B BUS (-) Circuit Open
Courtesy of CHRYSLER LLC
1. Measure the resistance of the (D54) CAN B BUS (-) circuit between the Totally Integrated Power Module C3 harness connector and the Amplifier C1 harness connector.
  Is the resistance below 2.0 Ohms?
  
  Yes
  - Replace the Amplifier in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure .
  No
  - Repair the CAN B BUS (-) circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure .