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Test Fa: Instantaneous Fuel Economy Always Reads 0 Mpg Or 99 Liters/100 Km

NOTE: Fuel Flow Signal (FFS) is generated by electronic engine controller (EEC-IV).

  1. Check Speedometer Operation

    Test drive vehicle to ensure speedometer/odometer works properly. If speedometer is functioning properly, go to next step. If speedometer is not functioning properly, go to TEST SF  .

  2. Check For Fuel Flow Pulses

    Turn ignition switch to RUN position. Select INSTANT ECONOMY function. Observe display. If display shows "FFS", go to next step. If display does not show "FFS", replace Electronic Instrument Cluster (EIC). See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION.

  3. Check Continuity Of Circuit 305 (Fuel Flow)

    Ensure continuity and absence of shorts in circuit 305 (Light Blue/Pink wire). See Figure . If continuity does not exist and/or shorts are found, repair circuit 305 (Light Blue/Pink wire) as required. If circuit is okay, replace or diagnose faulty electronic engine controller (EEC-IV) as required for operation of fuel flow circuit 305 (Light Blue/Pink wire).
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