BUS System Communication

BUS SYSTEM COMMUNICATION







- When Monitored:
Ignition ON, continuously.

- Set Condition:
When the CAB does not receive a message from the instrument cluster for 10 seconds.





1. BUS SYSTEM COMMUNICATION FAILURE DTC PRESENT
1. Turn the ignition on.
2. With the scan tool, read DTCs.
3. With the scan tool, read Freeze Frame information.
4. With the scan tool, erase DTCs.
5. Turn the ignition off.
6. Turn the ignition on.
7. With the scan tool, read DTCs.

Does the scan tool display BUS SYSTEM COMMUNICATION?

Yes

- Go To 2

No

- Go To 4

2. INSTRUMENT CLUSTER DTC PRESENT
1. Turn the ignition on.
2. With the scan tool, read EMIC DTCs.

Does the scan tool display ABS MESSAGE NOT RECEIVED?

Yes

- Refer to symptom ABS MESSAGE NOT RECEIVED in the BODY/INSTRUMENT CLUSTER category. ABS Messages Not Received
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Go To 3

3. BUS CIRCUIT OPEN




1. Turn the ignition off.
2. Disconnect the negative (-) battery cable.
3. Disconnect the CAB harness connector.

NOTE: check connector - Clean/repair as necessary.

4. Measure the resistance of the Bus circuit between the CAB connector and the Data Link Connector (DLC).

Is the resistance below 5.0 Ohms?

Yes

- Replace the Anti-Lock Brake Controller (CAB).
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Repair the Bus circuit for an open.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

4. INTERMITTENT CONDITION
1. Turn the ignition off.
2. Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
3. Visually inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals.

Were any problems found?

Yes

- Repair as necessary.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Test Complete.