Message Systems

U0019-CAN B BUS





For a complete wiring diagram refer to Diagrams/Electrical.

- When Monitored:

Continuously

- Set Condition:

Whenever the Can B Bus (+) or B Bus (-) circuit is open, shorted to voltage or shorted to ground, this code will set.





Diagnostic Test

1.TEST FOR INTERMITTENT CONDITION

Turn the ignition on.

With the scan tool, record and erase DTCs

Cycle the ignition from on to off 3 times.

Turn the ignition on.

With the scan tool, read DTCs.

Does the scan tool display: U0019-CAN B BUS CIRCUIT?

Yes

- Go To 2

No

- The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
- Perform BODY VERIFICATION TEST - VER 1.

2.CHECK FRONT CONTROL MODULE DTCs

With the scan tool, read Front Control Module DTCs

Does the scan tool display any CAN B BUS DTCs - ACTIVE?

Yes

- Refer to the symptom list for problems related to Communication.
-

No

- Go to 3
-

3.CAN B BUS (+) CIRCUIT OPEN





Turn the ignition off.

Disconnect the Compass Temperature Module (EOM) harness connector.

Disconnect the Front Control Module C1 harness connector.

Measure the resistance of the (D55) Can B Bus (+) circuit between the Front Control Module C1 harness connector and the Compass Temperature Module (EOM) harness connector.

Is the resistance below 2.0 ohms?

Yes

- Go To 4

No

- Repair the Can B Bus (+) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1.

4.CAN B BUS (-) CIRCUIT OPEN





Measure the resistance of the (D54) Can B Bus (-) circuit between the Front Control Module C1 harness connector and the Compass Temperature Module (EOM) harness connector.

Is the resistance below 2.0 ohms?

Yes

- Replace the Compass Temperature Module (EOM).
- Perform BODY VERIFICATION TEST - VER 1.

No

- Repair the Can B Bus (-) circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1.