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Ignition Relay Diagnosis

IGNITION RELAY DIAGNOSIS

CIRCUIT DESCRIPTION
The ignition relay supplies voltage to the following components:
^ Air pump relay
^ A/C CLU relay
^ Ignition Control Module (ICM)
^ Fuel injectors
^ Transmission solenoids
^ Mass Air Flow (MAF) sensor
^ All-wheel drive actuator
^ Air injection valve
^ Evaporative Emission (EVAP) solenoid
^ Oxygen Sensors (O2)
^ Brake pressure modulator valve

DIAGNOSTIC AIDS
If the ignition relay fails open:
^ Scan data will be available.
^ Vehicle will crank, but not start.
^ Dash indicator lights will illuminate.

TEST DESCRIPTION

Steps 1-11:




The numbers below refer to the step numbers on the diagnostic table.
5. This step is testing the relay ground circuit.
6. This step isolates the circuit from the ignition relay. All of the circuits at the relay are good if the test lamp illuminates.
10. Remove the underhood fuse relay center cover and inspect the circuits that are supplied voltage by the ignition relay, and the ignition relay ground circuits.