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Test Sb: Speedometer Reads "0" At All Speeds

NOTE: Whenever Electronic Instrument Cluster (EIC) is replaced, indicate previous odometer mileage on odometer sticker. Affix odometer sticker to driver inside door pillar.

  1. Verify Display (Prove Out Test)

    Turn ignition switch to RUN position. Observe cluster display. All segments should turn on, turn off and then normal display should appear. If display is working properly, go to next step. If display is not working properly, replace Electronic Instrument Cluster (EIC). See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION.

  2. Check Odometer

    Test drive vehicle. Ensure odometer advances mileage when vehicle is driven forward. If odometer does not advance, go to next step. If odometer advances and speedometer is inoperative, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION.

  3. Check Fuel Computer

    Test drive vehicle. Select TRIP DISTANCE on fuel computer. See FUEL COMPUTER DISPLAY under OPERATION. Distance should advance as vehicle is driven. If distance does not advance, go to next step. If distance advances and speedometer is inoperative, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION.

  4. Check Speed Control

    Test drive vehicle and check operation of speed control. If speed control is working, go to step  9 . If speed control does not work or vehicle is not equipped with speed control, go to next step.

  5. Check Wiring To Vehicle Speed Sensor (VSS)

    Disconnect Vehicle Speed Sensor (VSS) connector at transmission. Using DVOM to measure resistance, backprobe between VSS 2-pin harness connector terminals. If resistance is greater than 500 ohms, go to next step. If resistance is 500 ohms or less, repair short(s) in speed control/instrument cluster circuit 150 (Dark Green/White wire).

  6. Check Vehicle Speed Sensor (VSS) Resistance

    Using DVOM, measure resistance across VSS terminals. If reading is 200-230 ohms, go to next step. If resistance is not 200-230 ohms, replace VSS. Check speedometer operation.

  7. Check Driven Gear & Retainer Clip

    Remove VSS from transmission. Ensure driven gear teeth are in good condition and retainer clip is present. If VSS unit is okay, go to next step. If gear and/or clip are not okay, replace VSS unit.

  8. Check Drive Gear On Transmission

    Ensure all teeth of transmission output shaft drive gear are in good condition. If drive gear is functionally acceptable, go to next step. If drive gear is unacceptable, replace as required.

  9. Check Wiring To Cluster

    Reconnect VSS wiring harness connector. Remove EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. Using DVOM, measure resistance between EIC connector "B" terminals No. 12 circuit 150 (Dark Green/White wire) and No. 8 circuit 359 (Black/White wire). See Figure . Reading should be 160-230 ohms. If reading is as specified, replace EIC. See ELECTRONIC INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION. If reading is not 160-230 ohms, repair connectors and/or wiring of circuit 150 (Dark Green/White wire) from EIC to VSS. Recheck speedometer operation.
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