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ECM Power Source Circuit (Ignition Keyed)

  1. Ensure ECM ground circuits are okay. See ECM GROUND CIRCUITS . Remove glove box. Turn ignition on. Leave ECM connectors attached. See COMPONENT LOCATIONS  under INTRODUCTION. Backprobing connector, connect voltmeter negative lead to terminal No. 16 (Brown wire) of ECM connector E9 (this terminal is grounded). To identify ECM connectors and terminals, see Figure.
  2. Connect voltmeter positive lead to terminals No. 23 (Black/Orange wire) of ECM connector E10. If battery voltage is present, ECM power circuit is okay. If battery voltage is not present, check EFI main relay. See RELAYS  under MODULES, MOTORS, RELAYS & SOLENOIDS.
  3. If EFI main relay is okay, check EFI fuse. If EFI fuse is blown, check for short to ground in wiring. If EFI fuse is okay, check for open circuit between battery and EFI main relay, and between EFI main relay and ECM.
  4. If circuits are okay, check IGN fuse. If IGN fuse is blown, check for short to ground in wiring. If IGN fuse is okay, check ignition switch. See STEERING COLUMN SWITCHES article in ACCESSORIES/SAFETY EQUIPMENT section. If ignition switch is okay, repair open circuit between ignition switch and EFI main relay, or between EFI main relay and ground.
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