Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTIONThe ignition relay supplies voltage to the following components:
^ The ignition control modules (ICM)
^ The fuel injectors
^ The powertrain control module (PCM)
^ The mass airflow (MAF) sensor
^ Transmission control solenoids
^ The A/C clutch relay
DIAGNOSTIC AIDS
If the ignition relay fails to close, the following will occur:
^ The engine cranks, but does not run
^ The scan data will be available
^ The instrument panel lamps will illuminate
TEST DESCRIPTION
Steps 1-4:
Steps 5-11:
The numbers below refer to the step numbers on the diagnostic table:
2. This step is testing the battery positive voltage circuit of the ignition relay.
3. This step is testing the ignition 1 positive voltage circuit of the ignition relay.
4. This step is testing the coil ground circuit of the ignition relay.
5. This step isolates the circuit from the ignition relay. All of the circuits at the relay are good if the test lamp illuminates.