Restraints

U0019-CAN B BUS

U0019 - Can B Bus:

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 restraint controller (ORC)

Diagnostic Test

1. VERIFY DTC U0019-CAN B BUS IS ACTIVE

Turn the ignition on.
With the scan tool, read Occupant Restraint Controller (ORC) DTCs.

Q: Does the scan tool display active: U0019-CAN B BUS?

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. Occupant Restraint Controller (ORC) Verification Test

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

Q: Does the scan tool display any active CAN B BUS related DTCs?

YES: Diagnose and repair the DTC(s).
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.
- IF THE OCCUPANT RESTRAINT CONTROLLER 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 ORC C2 connector.

NOTE: Check connectors - Clean and repair as necessary.

Connect the Load Tool ORC 8443-24 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.

Q: Is the resistance below 2.0 ohms?

YES: Go To 4
NO: Repair the (D55) CAN B Bus (+) circuit for an open. Perform the AIRBAG SYSTEM VERIFICATION TEST - VER 1. Airbag System Verification Test




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.

Q: Is the resistance below 2.0 ohms?

YES: Replace the ORC.
NO: Repair the (D54) CAN B Bus (-) circuit for an open. Perform the AIRBAG SYSTEM VERIFICATION TEST - VER 1. Airbag System Verification Test