No Response From OCM (Occupant Classification Module)
*NO RESPONSE FROM OCM (OCCUPANT CLASSIFICATION MODULE)
For a complete wiring diagram refer to Diagrams/Electrical.
Diagnostic Test
1. TEST FOR INTERMITTENT CONDITION
NOTE: Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.
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.
NOTE: 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.
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. (A417) 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.
WARNING: 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 (A417) Fused B(+) circuit.
Does the test light illuminate brightly?
Yes
- Go To 3
No
- Repair the (A417) Fused B(+) circuit for an open or short.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test
3. (Z944) GROUND CIRCUIT OPEN
Turn the ignition off.
Using a 12-volt test light connected to 12-volts, check the (Z944) ground circuit.
Does the test light illuminate brightly?
Yes
- Go To 4
No
- Repair the (Z944) ground circuit for an open.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test
4. (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.
Turn the ignition on.
Measure the voltage between the (D54) CAN B Bus (-) circuit and ground.
Measure the voltage between the (D55) CAN B Bus (+) circuit and ground.
Is there any voltage present on either circuit?
Yes
- Go To 5
No
- Repair the (D55) and (D54) CAN B Bus circuits for an open. Inspect the connector for damage.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test
5. CHECK (R263) DRIVER SEAT POSITION SENSOR VOLTAGE CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off.
Measure the resistance between ground and the (R263) Driver Seat Position Sensor Voltage-Driver circuit.
Is the resistance below 10k ohms?
Yes
-
NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if the condition inspecting or testing for is present in the Seat Harness.
- Replace the OCM and Driver Seat Position Sensor Harness.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test
No
- Go To 6
6. CHECK (R701) SEAT WEIGHT SENSOR 5 VOLT CIRCUIT FOR A SHORT TO GROUND
Disconnect the Occupant Classification Module C2 harness connector.
Measure the resistance between ground and the (R701) Seat Weight Sensor 5 volt circuit.
Is the resistance below 10k ohms?
Yes
-
NOTE: Do not attempt to repair the Seat Harness. Replace the Seat Harness if the condition is present.
- Replace the OCM and Driver Seat Position Sensor Harness.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test
No
- Replace the Occupant Classification Module.
- Perform the OCS VERIFICATION TEST-VER 1. Occupant Classification Module (OCM) System Verification Test