U0019-CAN B BUS
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
With the Instrument Cluster awake.
- Set Condition:
Whenever the Can B Bus (+) or B Bus (–) circuit is open, shorted to voltage or shorted to ground, this code will set.
| Possible Causes |
| CAN B BUS DTCs IN FRONT CONTROL MODULE |
| (D54) CAN B BUS (–) CIRCUIT OPEN |
| (D55) CAN B BUS (+) CIRCUIT OPEN |
| INSTRUMENT CLUSTER |
Diagnostic Test
1. CHECK FOR AN ACTIVE DTCTurn 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.
Is the DTC active?
Yes
- Go To 2
No
- The condition that caused this code to set is not present at this time. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
- Perform BODY VERIFICATION TEST VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
2. CHECK FRONT CONTROL MODULE DTCs
With the scan tool, read Front Control Module DTCs.
Does the scan tool display the U0019–CAN B BUS DTC?
Yes
- Refer to the symptom list for problems related to Communication in the ELECTRICAL– ELECTRONIC CONTROL MODULES – ELECTRICAL DIAGNOSES section. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING)
No
- Go to 3
3. (D55) CAN B BUS (+) CIRCUIT OPEN
Turn the ignition off.
Disconnect the negative battery cable.
Disconnect the Instrument Cluster C3 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 Instrument Cluster C3 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. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
4. (D54) 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 Instrument Cluster C3 harness connector.
Is the resistance below 2.0 ohms?
Yes
- Replace the Instrument Cluster in accordance with the Service Information.
- Perform BODY VERIFICATION TEST VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)
No
- Repair the Can B Bus (–) circuit for an open.
- Perform BODY VERIFICATION TEST VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)