Radio

U0020-CAN B BUS OFF PERFORMANCE



- 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.





1. TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. Cycle the ignition from on to off three times.
4. Turn the ignition on.
5. With the scan tool, read DTCs.

Does the scan tool display: U0020-CAN B BUS OFF PERFORMANCE?

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 the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK FRONT CONTROL MODULE DTCs
1. With the scan tool, read Totally Integrated Power Module DTCs.

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

Yes

- Perform the appropriate diagnostic procedure. Testing and Inspection.

No

- Go To 3

3. CAN B BUS (+) CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the Radio 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 Radio harness connector.

Is the resistance below 2.0 Ohms?

Yes

- Go To 4

No

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

4. CAN B BUS (-) CIRCUIT OPEN
1. Measure the resistance of the (D54) CAN B BUS (-) circuit between the Totally Integrated Power Module C3 harness connector and the Radio harness connector.

Is the resistance below 2.0 Ohms?

Yes

- Replace the Radio.
- Perform the BODY VERIFICATION TEST. Body Verification Test

No

- Repair the CAN B BUS (-) circuit for an open.
- Perform the BODY VERIFICATION TEST. Body Verification Test