Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTIONThe ignition relay supplies battery positive voltage to the following components:
^ Oxygen sensors (O2S)
^ Fuel injectors
^ Mass air flow (MAF) sensors
^ Ignition coils/modules
^ Evaporative emission solenoids
DIAGNOSTIC AIDS
The following will occur if the ignition relay fails to close:
^ Scan tool data will be available.
^ Engine cranks, but does not run.
^ Instrument panel lights 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.