No Response From OCM

NO RESPONSE FROM OCM





For complete wiring diagram refer to the wiring section.

POSSIBLE CAUSES
- (A956) fused B(+) circuit open or shorted
- (Z917) ground circuit open
- (F201) fused ignition switch output circuit open or shorted
- (D55) and (D54) CAN B bus circuits open
- Occupant classification module


DIAGNOSTIC TEST

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.

NOTE:
- Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts. With the scan tool, select ECU view.
- A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.

Q: Does the scan tool display a red X next to the module?

YES: Go To 2
NO: The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent , pushed out, and corroded terminals.




2. (A956) FUSED B(+) CIRCUIT OPEN OR SHORTED

WARNING:
- TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BEFORE PROCEEDING. DISCONNECT THE OCCUPANT CLASSIFICATION MODULE C1 HARNESS CONNECTOR.
- TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNITION ON, THEN RECONNECT THE BATTERY.

Using a 12-volt test light connected to ground, check the (A956) Fused B(+) circuit.

Q: Does the test light illuminate brightly?

YES: Go To 3
NO: Repair the (A956) Fused B(+) circuit for an open or short. Perform AIRBAG VERIFICATION TEST - VER 1.




3. (Z917) GROUND CIRCUIT OPEN
Turn the ignition off.
Using a 12-volt test light connected to 12-volts, check the (Z917) ground circuit.

Q: Does the test light illuminate brightly?

YES: Go To 4
NO: Repair the (Z917) ground circuit for an open. Perform AIRBAG VERIFICATION TEST - VER 1.




4. (F201) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED
Turn the ignition on.
Using a 12-volt test light connected to ground, check the (F201) Fused Ignition Switch Output circuit.

Q: Does the test light illuminate brightly?

YES: Go To 5
NO: Repair the (F201) Fused Ignition Switch Output circuit for an open or short. Perform AIRBAG VERIFICATION TEST - VER 1.




5. (D55) AND (D54) CAN B BUS CIRCUITS OPEN

WARNING: IF THE OCCUPANT CLASSIFICATION MODULE IS DROPPED AT ANY TIME, IT MUST BE REPLACED. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND PERSONAL INJURY OR DEATH.

NOTE: One open circuit will not cause this condition.

Measure the voltage between the (D54) CAN B Bus (-) circuit and ground.
Measure the voltage between the (D55) CAN B Bus (+) circuit and ground.

Q: Is there any voltage present on either circuit?

YES: Replace the Occupant Classification Module in accordance with the service information. Perform AIRBAG VERIFICATION TEST - VER 1.
NO: Repair the (D55) and (D54) CAN B Bus circuits for an open. Inspect the connector for damage. Perform AIRBAG VERIFICATION TEST - VER 1.