J - Testing Notes

NOTE: You should enter this Pinpoint Test only when you have been directed here from Quick Test or Pinpoint Test AA.

REMEMBER


This Pinpoint Test is intended to diagnose only the following:


- Fuel Pump Relay

- Inertia Switch

- Harness circuits: BATT(+), VPWR, FP, GND and Power-to-pumps

- Processor assembly


DESCRIPTION



The Fuel Pump Relay is a normally open relay that is used to supply voltage to the electric fuel pump. When the ignition key is turned to START or RUN position, the processor grounds Pin 22 (FP), which activates the relay (closes the contacts) and sends voltage to the fuel pump. If, within 1-2 seconds, the processor does not receive an ignition PIP signal (indicating the engine is not turning), Pin 22 will be ungrounded and the fuel pump will turn off.

The Inertia Switch is a safety device that is wired into either the primary circuit (coil side) or secondary circuit (contact side). In the event of a collision the inertia switch will open and voltage will be cut off to the fuel pump.