Vehicle Theft Security

U0019-CAN B BUS





For a complete wiring diagram Refer to Diagrams/Electrical.


- When Monitored:
Continuously

- Set Condition:
If the CAN B Bus (+) or CAN B Bus (-) circuit is open, shorted to voltage, or shorted to ground.







Diagnostic Test


1. VERIFY THAT THE DTC IS ACTIVE
Turn the ignition on.
With the scan tool, read the active DTCs.
Cycle the ignition switch from off to on at least 5 times, leaving the ignition on for a minimum of 90 seconds per cycle.
With the scan tool, read the active DTCs.
Does the scan tool display this DTC as active?

Yes


- Go To 2


No


- If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
-



2. CHECK FOR FRONT CONTROL MODULE DTCs
With the scan tool, read Front Control Module active DTCs
Does the scan tool display any CAN B BUS DTCs - ACTIVE?

Yes


- Diagnose and repair the active DTC(s).


No


- Go To 3
-



3. CHECK THE (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN
Turn the ignition off.
Disconnect the negative battery cable.
Disconnect the SKREEM harness connector.
Disconnect the Front Control Module harness connector.
Measure the resistance of the (D55) CAN B Bus (+) circuit between the Front Control Module harness connector and the SKREEM harness connector.
Is the resistance below 2.0 ohms?

Yes


- Go To 4


No


- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test .



4. CHECK THE (D54) CAN B BUS (-) CIRCUIT FOR AN OPEN
Measure the resistance of the (D54) CAN B Bus (-) circuit between the Front Control Module harness connector and the SKREEM harness connector.
Is the resistance below 2.0 ohms?

Yes


- Replace the SKREEM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test .


No


- Repair the (D54) CAN B Bus (-) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test .