Chart A-5 Fuel Injector Circuit Check

Chart A-5:

Fuel Injector Circuit:

CIRCUIT DESCRIPTION:
When the solenoid coil of the fuel injector is energized by the engine control module ECM, it will activate the plunger and pressurized fuel will be injected into the throttle body. The fuel pump will operate as long as the engine is cranking, and the ECM is receiving ignition reference pulses.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. Checks to see if the ECM is controlling the fuel injector signals.

2. Checks the fuel injector for correct resistance.

3. Checks for voltage at fuel injector.

4. Checks for an open or short to ground in YEL/BLK wire, a faulty ECM or a faulty fuel injector.

5. Checks for an open or short to ground in YEL wire, an open in WHT/BLU wire or a faulty fuel injector resistor.

DIAGNOSTIC AIDS:
There may be fuel spray at the fuel injector, but it may not be enough to start the engine. If both the fuel injector and the circuit are OK, the fuel injector nozzle may be partly blocked.