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B212C






B212C-IGNITION RUN/START INPUT CIRCUIT OPEN

Special Tools:










For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Occupant Restraint Controller module (ORC) receives power from both a fused run relay output and fused ignition switch output circuit from the Totally Integrated Power Module (TIPM). These circuits power the ORC and the capacitors used to initiate the squib deployment circuits in the event of collision detection.

- When Monitored:
he ORC monitors the voltage on the Run/Start and Run circuits and compares their voltage at power up during the initialization process, and once every 100 ms throughout the ignition cycle.

- Set Condition:
If voltage on the (F201) Fused Ignition Switch Output (Run-Start) circuit drops below 6.0 volts for 15 seconds. The DTC will change from active to stored when the (F201) Fused Ignition Switch Output (Run-Start) circuit voltage stays above 6.0 volts for 5 seconds.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Restraints System Pre-Diagnostic Procedure.

NOTE: The airbag warning lamp in the Cab Compartment Node/CCN (Instrument Cluster) sets.

1. VERIFY THAT DTC B212C-IGNITION RUN/START INPUT CIRCUIT OPEN IS ACTIVE IN THE ORC

NOTE: Make sure the battery is fully charged.

1. Turn the ignition on.
2. With the scan tool, read ORC DTCs.

Does the scan tool display active: B212C-IGNITION RUN/START INPUT CIRCUIT OPEN?

Yes

- Go To 2

No

- Perform the RESTRAINTS SYSTEM INTERMITTENT TEST. Restraints System Intermittent Condition Test.

2. INSPECT THE AIRBAG RUN-START FUSE
1. Turn the ignition off.

WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

2. Remove the Airbag Run-Start Fuse 29 from the TIPM and inspect the fuse.

NOTE: Check the connectors - Clean and repair as necessary.

Is the Run/Start fuse open?

Yes

- Go To 3

No

- Go To 5

3. CHECK (F201) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE




1. Measure the resistance of the (F201) Fused Ignition Switch Output (Run-Start) circuit between ground and the Airbag Run-Start fuse terminal (output).

Is the resistance below 100.0 Ohms?

Yes

- Go To 4

No

- Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors. Look for chafed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals.Replace Airbag Run-Start Fuse.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

4. CHECK THE (F201) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE WITH THE ORC CONNECTORS DISCONNECTED





WARNING: 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 serious or fatal injury.

WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Disconnect both ORC connectors.

NOTE: Check the connectors - Clean and repair as necessary.

2. Connect the (8443-24) to the ORC C2 connector.
3. Measure the resistance of the (F201) Fused Ignition Switch Output (Run-Start) circuit between the appropriate terminal of the (8443-24) and ground.

Is the resistance below 100.0 Ohms?

Yes

- Repair the (F201) Fused Ignition Switch Output (Run-Start) circuit for a short to ground.
- Replace the TIPM Airbag Run-Start Fuse.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test

No

- Replace the Occupant Restrain Controller (ORC). Occupant Restraint Controller - Removal.
- Replace the TIPM Airbag Run-Start Fuse.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

5. CHECK (F944) IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN



If equipped with the standard key ignition, use this ignition on warning.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If equipped with the keyless ignition, use this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Turn the ignition on.
2. Measure the voltage between Ground and the appropriate terminal of the (F944) Ignition Switch Output (Run-Start) circuit at the Airbag Run-Start fuse terminal (supply).

Is the voltage above 6.0 volts?

Yes

- Go To 6

No

- Repair the open (F944) Ignition Switch Output (Run-Start) circuit.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

6. CHECK (F201) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN





WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

1. Reinstall the Airbag Run-Start Fuse.
2. Disconnect both ORC connectors.

NOTE: Check connectors - Clean and repair as necessary.

3. Install the (8443-24) to the ORC C2 connector.If equipped with the standard key ignition, use this ignition on warning.

WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If equipped with the keyless ignition, use this ignition on warning.

WARNING: Disconnect the 12-volt battery wait two minutes before proceeding, remove the ORC fuses, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the ORC fuses. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.

4. Measure the voltage of the (F201) Fused Ignition Switch Output (Run-Start) Circuit between the appropriate terminal of the (8443-24) and ground.

Is the voltage above 6.0 volts?

Yes

- Replace the Occupant Restrain Controller (ORC). Occupant Restraint Controller - Removal.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.

No

- Repair the (F201) Fused Ignition Switch Output (Run-Start) circuit for an open.
- Perform the RESTRAINTS SYSTEM VERIFICATION TEST. Restraints System Verification Test.