U0019-CAN B BUS-OCM
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
Continuously
- Set Condition:
Whenever the CAN B Bus (+) or CAN B Bus (-) circuit is open, shorted to voltage, or shorted to ground.
| Possible Causes |
| ACTIVE U0019 CAN B BUS DTC IN FRONT CONTROL MODULE |
| (D55) CAN B BUS (+) CIRCUIT OPEN |
| (D54) CAN B BUS (-) CIRCUIT OPEN |
| OCCUPANT CLASSIFICATION MODULE (OCM) |
Diagnostic Test
1. VERIFY DTC U0019-CAN B BUS–OCM IS ACTIVETurn the ignition on.
With the scan tool, read Occupant Classification Module (OCM) DTCs.
Does the scan tool display active: U0019-CAN B BUS–OCM?
Yes
- Go To 2
No
- If the DTC is stored, 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 *OCS VERIFICATION TEST - VER 1.
2. CHECK FOR ACTIVE CAN B BUS RELATED DTCS IN THE FRONT CONTROL MODULE (FCM)
With the scan tool, read Front Control Module (FCM) DTCs
Does the scan tool display any active CAN B BUS related DTCs?
Yes
- Diagnose and repair the DTC(s). (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - DIAGNOSIS AND TESTING)
No
- Go To 3
3. CHECK (D55) CAN B BUS (+) CIRCUIT FOR AN OPEN
WARNING: To avoid personal injury or death, turn the ignition off, disconnect the battery and wait two minutes before proceeding.
WARNING: If the Occupant Classification Module is dropped at any time, it must be replaced. Failure to take the proper precautions can result in accidental airbag deployment and personal injury or death.
Disconnect the OCM C1 connector.
NOTE: Check connectors - Clean and repair as necessary.
Disconnect the Front Control Module (FCM) C1 connector.
Measure the resistance of the (D55) CAN B Bus (+) circuit between the Front Control Module C1 connector and the OCM C1 connector.
Is the resistance below 2.0 ohms?
Yes
- Go To 4
No
- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform *OCS VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)
4. CHECK (D54) CAN B BUS (–) CIRCUIT FOR AN OPEN
Measure the resistance of the (D54) CAN B Bus (–) circuit between the Front Control Module C1 connector and the OCM, C1 connector.
Is the resistance below 2.0 ohms?
Yes
- Replace the OCM in accordance with the Service Information.
- Perform OCS VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)
No
- Repair the (D54) CAN B Bus (–) circuit for an open.
- Perform OCS VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)