Diagnostic Test

1) VERIFY THAT DTC B212C IGNITION RUN/START INPUT CIRCUIT OPEN IS ACTIVE IN THE ORC.
NOTE: Ensure the battery is fully charged.

NOTE: When reconnecting Airbag system components, the ignition must be turned off and the battery must be disconnected.

Turn the ignition on.

Record and erase all ORC DTC's.

Wait 10 seconds.

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

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

Yes
1. Go To 2).
No
1. Go To 7).
2) INSPECT AIRBAG RUN-START FUSE

Fig 1: Inspecting Airbag Run-Start Fuse
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Remove the Airbag Run-Start Fuse 29 from the Integrated Power Module and inspect the fuse.

NOTE: Check connectors - Clean and repair as necessary.

Is the Run/Start fuse open?

Yes
1. Go To 3).
No
1. Go To 5).
3) CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE

Fig 2: Checking Fused Ignition Switch Output (RUN-START) Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (F20) Fused Ignition Switch Output (Run-Start) circuit between ground and the Airbag Run-Start fuse terminal (output side).

Is the resistance below 100.0 ohms?

Yes
1. Go To 4).
No
1. 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.
2. Replace Airbag Run-Start Fuse.
3. Perform *ORC VERIFICATION TEST - VER 1 .
4) CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE WITH ORC CONNECTORS DISCONNECTED

Fig 3: Checking Fused Ignition Switch Output (RUN-START) Circuit
Courtesy of DAIMLERCHRYSLER CORP.

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 personal injury or death.

WARNING: To avoid personal injury or death, turn the ignition off, disconnect the battery and wait two minutes before proceeding.

Disconnect both ORC connectors.

NOTE: Check connectors - Clean and repair as necessary.

Connect the Load Tool ORC 8443-24 Adaptor to the ORC C2 connector.

Measure the resistance of the (F20) Fused Ignition Switch Output (Run-Start) circuit between the 8443-24 adaptor and ground).

Is the resistance below 100.0 ohms?

Yes
1. Repair the (F20) Fused Ignition Switch Output (Run-Start) circuit for a short to ground.
2. Replace the Airbag Run-Start Fuse.
3. Perform *ORC VERIFICATION TEST - VER 1 .
No
1. Replace the ORC in accordance with the Service Information.
2. Replace the Airbag Run-Start Fuse.
3. Perform *ORC VERIFICATION TEST - VER 1 .
5) CHECK (F944) IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN

Fig 4: Checking Ignition Switch Output (RUN-START) Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition on.

Measure the voltage between Ground and the (F944) Ignition Switch Output (Run-Start) circuit at the Airbag Run-Start fuse terminal (supply side).

Is the voltage above 6.0 volts?

Yes
1. Go To 6).
No
1. Repair the (F944) Ignition Switch Output (Run-Start) circuit for an open.
2. Perform *ORC VERIFICATION TEST - VER 1 .
6) CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN

Fig 5: Checking Fused Ignition Switch Output (RUN-START) Circuit
Courtesy of DAIMLERCHRYSLER CORP.

WARNING: To avoid personal injury or death, turn the ignition off, disconnect the battery and wait two minutes before proceeding.

Reinstall the Airbag Run-Start Fuse.

Disconnect the both ORC connectors.

NOTE: Check connectors - Clean and repair as necessary.

Install the Airbag Load tool ORC 8443-24 adaptor to the ORC C2 connector.

WARNING: To avoid personal injury or death, turn the ignition on, then reconnect the battery.

Measure the voltage of the (F20) Fused Ignition Switch Output (Run-Start) Circuit between the 8443-24 connector and ground.

Is the voltage above 6.0 volts?

Yes
1. Replace the ORC in accordance with the Service Information.
2. Perform *ORC VERIFICATION TEST - VER 1 .
No
1. Repair the (F20) Fused Ignition Switch Output (Run-Start) circuit for an open.
2. Perform *ORC VERIFICATION TEST - VER 1 .
7) TEST FOR INTERMITTENT CONDITION
With the scan tool, record and erase all DTCs from all Airbag modules.

If any ACTIVE codes are present they must be resolved before diagnosing any stored codes.

WARNING: To avoid personal injury or death, turn the ignition off, disconnect the battery and wait two minutes before proceeding.

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.

Look for chafed, pierced, pinched, or partially broken wires and broken, bent, pushed out, spread, corroded, or contaminated terminals.

The following additional checks may assist you in identifying a possible intermittent problem.

Reconnect any disconnected components and harness connector.

WARNING: To avoid personal injury or death, turn the ignition on, then reconnect the battery.

With the scan tool, monitor active codes as you work through the following steps.

WARNING: To avoid personal injury or death, maintain a safe distance from all airbags while performing the following steps.

Wiggle the wiring harness and connectors of the related airbag circuit or component.

If codes are related to the Driver Airbag circuits, rotate the steering wheel from stop to stop.

If only stored codes return, continue the test until the problem area has been isolated.

In the previous steps you have attempted to recreate the conditions responsible for setting the active DTC in question.

Does the scan tool display any ACTIVE DTCs?

Yes
1. Select appropriate symptom from DIAGNOSTIC CODE INDEX .
No
1. No problem found. Erase all codes before returning the vehicle to the customer.