Ignition Relay: Testing and Inspection

CIRCUIT DESCRIPTION
The ignition relay supplies battery voltage to the following components:
^ The oxygen sensors (HO2S)
^ The ignition control modules (ICM)/coils
^ The fuel injectors
^ The mass airflow (MAF) sensor

DIAGNOSTIC AIDS
The following may occur if the ignition relay fails to close:
^ Engine cranks, but does not run
^ The scan tool data will be available.
^ The instrument panel (IP) indicator will illuminate.

TEST DESCRIPTION

Steps 1-5:

Steps 6-11:

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.