Diagnostic Test

VERIFY DTC U0019-CAN B BUS IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, read PLGM 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 chaffed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE FRONT CONTROL MODULE (FCM)
1. With the scan tool, read Front Control Module (FCM) DTCs
  Does the scan tool display any active CAN B BUS related DTCs?
  
  Yes
  - Perform the appropriate diagnostic procedure. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - 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.
3. Disconnect the Power Liftgate Module C2 connector.
4. Disconnect the Front Control Module (FCM) C1 harness connector.
5. Measure the resistance of the (D55) CAN B Bus (+) circuit between the Front Control Module C1 harness connector and the Power Liftgate Module C2 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 BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
CHECK (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO THE (D55) CAN B BUS (+) CIRCUIT

Fig 2: Checking CAN B BUS (-) Circuit For A Short To CAN B BUS (+) Circuit
Courtesy of CHRYSLER LLC
1. Measure the resistance between the (D54) CAN B Bus (-) circuit and the (D55) CAN B Bus (+) circuit in the Power Liftgate Module C2 harness connector.
  Is the resistance below 2.0 ohms?
  
  Yes
  - Repair the (D54) CAN B Bus (-) circuit for a short to the (D55) CAN B Bus (+) circuit.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
  No
  - Go to step 5
CHECK (D54) CAN B BUS (-) CIRCUIT FOR AN OPEN

Fig 3: 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 Front Control Module C1 connector and the Power Liftgate Module C2 connector.
  Is the resistance below 2.0 ohms?
  
  Yes
  - Go to step 6
  No
  - Repair the (D54) CAN B Bus (-) circuit for an open.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
CHECK THE (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO VOLTAGE

Fig 4: Checking CAN B BUS (-) Circuit For A Short To Voltage
Courtesy of CHRYSLER LLC
1. Turn the ignition on.
2. Measure the voltage of the (D54) CAN B Bus (-) circuit.
  Is there any voltage present?
  
  Yes
  - Repair the (D54) CAN B Bus (-) circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
  No
  - Go to step 7
CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO VOLTAGE

Fig 5: Checking CAN B BUS (+) Circuit For A Short To Voltage
Courtesy of CHRYSLER LLC
1. Measure the voltage of the (D55) CAN B Bus (+) circuit.
  Is there any voltage present?
  
  Yes
  - Repair the (D55) CAN B Bus (+) circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
  No
  - Go to step 8
CHECK THE (D54) CAN B BUS (-) CIRCUIT FOR A SHORT TO GROUND

Fig 6: Checking CAN B BUS (-) Circuit For A Short To Ground
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Measure the resistance between ground and the (D54) CAN B Bus (-) circuit.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the (D54) CAN B Bus (-) circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
  No
  - Go to step 9
CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR A SHORT TO GROUND

Fig 7: Checking CAN B BUS (+) Circuit For A Short To Ground
Courtesy of CHRYSLER LLC
1. Measure the resistance between ground and the (D55) CAN B Bus (+) circuit in the PLG C2 connector.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the (D55) CAN B Bus (+) circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
  No
  - Replace the Power Liftgate Module in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .