Diagnostic Test

VERIFY DTC U0020-CAN B BUS IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, read Occupant Classification Module (OCM) DTCs.
  Does the scan tool display active: U0019-CAN B BUS?
  
  Yes
  - Go to step 2
  No
  - If the DTC is stored, check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded or contaminated terminals.
  - Perform the OCS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE TOTALLY INTEGRATED POWER MODULE (TIPM)
1. With the scan tool, read the Totally Integrated Power (TIPM) DTCs
  Does the scan tool display any active CAN B BUS related DTCs?
  
  Yes
  - Diagnose and repair the DTC(s). Refer to DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Diagnosis and Testing .
  No
  - Go to step 3
CHECK (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN

Fig 1: Checking CAN B BUS (+) Circuit For An Open
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the negative battery cable.
  WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
3. Disconnect the OCM connectors.
4. Disconnect the TIPM C3 harness connector.
5. Measure the resistance of the (D55) CAN B Bus (+) circuit between the TIPM C3 harness connector and the OCM C1 harness connector.
  Is the resistance below 2.0 Ohms?
  
  Yes
  - Go to step 4
  No
  - Repair the (D55) CAN B Bus (+) circuit for an open.
  - Perform the OCCUPANT CLASSIFICATION MODULE SYSTEM VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Occupant Classification (OCM) - Standard Procedure .
CHECK (D54) CAN B BUS (-) CIRCUIT FOR AN OPEN

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