Except California Specification Vehicles
SYSTEM: injector CircuitWIRING DIAGRAM
CIRCUIT DESCRIPTION
The injectors are provided to the intake manifold. They inject fuel into the cylinders based on the signals from the engine control module (ECM).
DIAGNOSTIC PROCEDURE
1. Check voltage of terminals #10 and #20.
^ If OK proceed to step 3.
^ If not OK proceed to step 2.
2. Check AM2 fuse.
^ If OK check for open in harness and connector between ECM and battery.
^ If not OK check for short Circuits in all the harness and components connected to AM2 fuse.
Refer to included WIRING DIAGRAM
3. Check continuity between terminals E01, E02 and body ground.
^ If OK proceed to step 4.
^ If not OK repair or replace harness or connector.
4. Check operation for injectors.
^ If OK check and replace ECM.
^ If not OK replace injector.
INSPECTION USING OSCILLOSCOPE
Fuel Injector Power Circuit:
Injector Signal Waveform
^ With the engine idling measure waveform between terminals #10, #20 and E01 of engine control module.
HINT: The correct waveform appears as shown in the illustration above.