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Ignition Relay Diagnosis

CIRCUIT DESCRIPTION
The ignition relay supplies ignition voltage to the following components:
^ The fuel injectors
^ The ignition coils
^ The Powertrain Control Module (PCM)
^ The alternator/generator

DIAGNOSTIC AIDS
If the IGN relay fails open:
^ Scan data WILL be available
^ The vehicle WILL crank, no start
^ The dash indicator lights WILL illuminate

TEST DESCRIPTION

Steps 1-5:




Steps 6-11:




The numbers below refer to the step numbers on the diagnostic table.
2. Refer to the Thumbnail Schematic for proper relay terminal identification.
4. This step is testing the relay ground circuit.
5. This step isolates the circuit from the IGN relay. All of the circuits at the relay are good if the test lamp illuminates.
9. The open circuit will be between the splice and the IGN relay.
10. Remove the underhood electrical center cover and inspect the circuits that are supplied a voltage by the IGN relay.