1990 Mercury Cougar LSFACTORY OEM SERVICE PROCEDURE

EEC-IV Processor Spout Circuit Check

  1. With ignition off, remove EEC-IV processor wire harness connector. Connect LED test light between breakout box terminals No. 36 and No. 60.
  2. Crank engine while observing test light. If test light blinks while engine is cranking, replace EEC-IV processor. If test light does not blink while engine is cranking, turn ignition off.
  3. Remove diagnostic cable connector from DIS module. Connect LED test light between breakout box terminals No. 36 and No. 60. Turn ignition on. If test light comes on, check for SPOUT short to VBAT. See Figure .
  4. If test light does not come on, connect LED test light between breakout box terminals No. 36 and No. 57. Turn ignition on. If test light comes on, check for SPOUT short to ground. If test light does not come on, replace DIS module.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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