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Pinpoint Test H: Speedometer

NOTE: Go to TROUBLE SHOOTING  before starting pinpoint test. Identify system where problem is located. Find symptom in trouble shooting and go to specific pinpoint test step as directed by trouble shooting procedure.

  1. Check Fuse

    Turn key OFF. Check the 10A METER fuse located in the interior fuse panel. Is the fuse OK? If yes, go to step  4 . If no, go to next step.

  2. Check System

    Turn key OFF. Replace the 10A METER fuse. Turn key ON. Does the fuse fail again? If yes, go to next step. If no, go to step  4 .

  3. Check For Short To Ground

    Turn key OFF. Remove the 10A METER fuse. Locate and disconnect the black 12-pin instrument cluster connector. Measure the resistance of the (Gray/Blue) wire between the right hand terminal of the 10A METER fuse holder and ground. Is the resistance less than 5 ohms? If yes, service the (Gray/Blue) wire. If no, replace the 10A METER fuse. Go to next step. See WIRING DIAGRAMS  .

  4. Check Power Supply To Instrument Cluster

    Turn key OFF. Disconnect the black 12-pin instrument cluster connector. Turn key ON. Measure the voltage of the (Gray/Blue) wire at the black 12-pin instrument cluster connector. Is the voltage greater than 10 volts? If yes, go to next step. If no, service the (Gray/Blue) wire. See WIRING DIAGRAMS  .

  5. Check Power Supply To Speedometer

    Turn key OFF. Reconnect the black 12-pin instrument cluster connector. Turn key ON. Measure the voltage on the B screw terminal at the back of the speedometer on the instrument cluster printed circuit board. Is the voltage greater than 10 volts? If yes, go to next step. If no, replace the instrument cluster printed circuit board.

  6. Check Speedometer Ground

    Turn key OFF. Disconnect the black 12-pin instrument cluster connector. Measure the resistance of the (Black) wire between the black 12-pin instrument cluster connector and ground. Is the resistance less than 5 ohms? If yes, go to next step. If no, service the (Black) wire. See WIRING DIAGRAMS  .

  7. Check Wires Between Vehicle Speed Sensor And Instrument Cluster

    Turn key OFF. Disconnect the black 12-pin instrument cluster connector and the vehicle speed sensor connector. Measure the resistance of the (Pink/Blue) wire between the vehicle speed sensor connector and the black 12-pin instrument cluster connector. Measure the resistance of the (Black)-(Black/Red) wire between the vehicle speed sensor connector and the black 12-pin instrument cluster connector. Measure the resistance of the (Pink/Blue) wire between the black 12-pin instrument cluster connector and ground. Is the resistance less than 5 ohms between the vehicle speed sensor connector and the black 12-pin instrument cluster connector for both wires, and greater than 10,000 ohms between the black 12-pin instrument cluster connector and ground for the (Black/Blue) wire? If yes, go to next step. If no, service the wire(s) in question. See WIRING DIAGRAMS  .

  8. Check Vehicle Speed Sensor Supply To Speedometer

    Turn key OFF. Disconnect the black 12-pin, white 12-pin and 10-pin instrument cluster connectors. Measure the resistance between the screw terminals at the back of the speedometer on the instrument cluster printed circuit board and the black 12-pin instrument cluster connector terminals on the instrument cluster. See VEHICLE SPEED SENSOR SUPPLY TO SPEEDOMETER RESISTANCE  . Are the resistances OK? If yes, go to next step. If no, replace the instrument cluster printed circuit board.
    VEHICLE SPEED SENSOR SUPPLY TO SPEEDOMETER RESISTANCE

    Speedometer Terminal Instrument Cluster Connector Terminal Resistance
    8 2G Less than 5 ohms
    G 2C Less than 5 ohms

  9. Check Vehicle Speed Sensor

    Turn key OFF. Reconnect the black 12-pin, white 12-pin and 10-pin instrument cluster connectors, and the vehicle speed sensor connector. Connect a Rotunda Digital Volt-Ohmmeter (105-00051) or equivalent between the S screw terminal on the back of the instrument cluster printed circuit board and ground. Place the voltmeter in the AC voltage position. Drive the vehicle at the speeds indicated in chart. See VEHICLE SPEED SENSOR VOLTAGE CHART  . Verify their corresponding voltage. Are the voltages correct? If yes, replace the speedometer. If no, replace the vehicle speed sensor.
    VEHICLE SPEED SENSOR VOLTAGE CHART

    Speed Km/H (mph) Approximate AC Voltage (volts)
    0 (0) 0
    8 (5) 0.5
    16 (10) 1.0
    24 (15) 1.6
    32 (20) 2.0
    40 (25) 2.4
    48 (30) 2.8
    56 (35) 3.1
    64 (40) 3.4
    72 (45) 3.6
    80 (50) 3.9
    88 (55) 4.2
    96 (60) 4.4
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