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Jeep Grand Cherokee WK. Manual - part 628

B212C-IGNITION RUN/START INPUT CIRCUIT OPEN (CONTINUED)

For the Airbag System circuit diagram (Refer to 8 - ELECTRICAL/RESTRAINTS - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition in the Run-Start position.

•

Set Condition:
If voltage on the (F20) Fused Ignition Switch Output (Run-Start) circuit drops below 6.0 volts.

Possible Causes

(F20) FUSED GNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN

(F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT SHORTED TO GROUND

(F944) IGNITION SWITCH OUTPUT CIRCUIT OPEN

OPEN IPM FUSE #29

OCCUPANT RESTRAINT CONTROLLER (ORC)

Diagnostic Test

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

>> Go To 2

>> Go To 7

INSPECT AIRBAG RUN-START FUSE

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

>> Go To 3

>> Go To 5

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RESTRAINTS - ELECTRICAL DIAGNOSTICS

B212C-IGNITION RUN/START INPUT CIRCUIT OPEN (CONTINUED)

CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE

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

Is the resistance below 100.0 ohms?

Yes

>> Go To 4

>> Using the wiring diagram/schematic as a guide, inspect

the related wiring and connectors. Look for chaffed,
pierced, pinched, or partially broken wires and broken,
bent, pushed out, spread, corroded, or contaminated ter-
minals.

Replace Airbag Run-Start Fuse.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 -
ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TEST-
ING)

CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT RESISTANCE WITH 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 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 connec-
tor.

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

>> Repair the (F20) Fused Ignition Switch Output (Run-Start)

circuit for a short to ground.

Replace the Airbag Run-Start Fuse.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS
AND TESTING)

>> Replace the ORC in accordance with the Service Information.

Replace the Airbag Run-Start Fuse.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS
AND TESTING)

RESTRAINTS - ELECTRICAL DIAGNOSTICS

8O - 335

B212C-IGNITION RUN/START INPUT CIRCUIT OPEN (CONTINUED)

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

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

>> Go To 6

>> Repair the (F944) Ignition Switch Output (Run-Start) circuit

for an open.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 -
ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TEST-
ING)

CHECK (F20) FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT FOR AN OPEN

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 con-
nector.

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

>> Replace the ORC in accordance with the Service Informa-

tion.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 -
ELECTRICAL/RESTRAINTS - DIAGNOSIS AND TESTING)

>> Repair the (F20) Fused Ignition Switch Output (Run-Start) circuit for an open.

Perform ORC VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/RESTRAINTS - DIAGNOSIS
AND TESTING)

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RESTRAINTS - ELECTRICAL DIAGNOSTICS

B212C-IGNITION RUN/START INPUT CIRCUIT OPEN (CONTINUED)

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 min-
utes before proceeding.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.

Look for chaffed, 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 ques-
tion.

Does the scan tool display any ACTIVE DTCs?

Yes

>> Select appropriate symptom from Symptom List.

>> No problem found. Erase all codes before returning the vehicle to the customer.

RESTRAINTS - ELECTRICAL DIAGNOSTICS

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