Chart A-1 No Service Engine Soon Light

Chart A-1 No MIL (Service Engine Soon):

No MIL (Service Engine Soon):

CIRCUIT DESCRIPTION
There should always be a steady Malfunction Indicator Lamp (MIL) with the ignition "ON" and engine "OFF." Switched battery voltage is supplied to the lamp. The Powertrain Control Module (PCM) will control the lamp and turn it "ON" by providing a ground path through CKT 419.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. If the fusible link is open, refer to wiring diagrams for complete circuit.
2. Using a test light connected to 12 volts, probe each of the system ground circuits and check that a good ground is present. Refer to "PCM Terminal End View" for PCM pin locations of ground circuits.

DIAGNOSTIC AIDS
If the engine operates OK, check:
^ Faulty light bulb.
^ CKT 419 open.
^ Gauges fuse open. This will result in no brake warning light, oil or generator lights, seat belt reminder, etc.