U0020-CAN B BUS OFF PERFORMANCE-ORC
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 U0020 CAN B BUS DTC IN OCCUPANT CLASSIFICATION MODULE |
| (D55) CAN B BUS (+) CIRCUIT OPEN |
| (D54) CAN B BUS (-) CIRCUIT OPEN |
| OCCUPANT RESTRAINT CONTROLLER (ORC) |
Diagnostic Test
1. VERIFY DTC U0020-CAN B BUS OFF PERFORMANCE–ORC IS ACTIVETurn the ignition on.
With the scan tool, read Occupant Restraint Controller (ORC) DTCs.
Does the scan tool display active: U0020-CAN B BUS OFF PERFORMANCE–ORC?
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 *ORC VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)
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
Turn the ignition off.
Disconnect the negative battery cable.
Disconnect the ORC C1 and C2 connector.
Connect the 8443-24 ORC Adaptor to the ORC C2 connector.
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 ORC C2 connector.
Is the resistance below 2.0 ohms?
Yes
- Go To 4
No
- Repair the (D55) CAN B Bus (+) circuit for an open.
- Perform *ORC 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 ORC C2 connector.
Is the resistance below 2.0 ohms?
Yes
- Replace the ORC in accordance with the Service Information.
- Perform *ORC VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)
No
- Repair the (D54) CAN B Bus (–) circuit for an open.
- Perform *ORC VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)