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Speedometer & Tachometer

  1. Using a voltmeter, check if voltage signal is present at speedometer and tachometer. If signal is present, voltage should measure half of ignition voltage. If signal circuit is open, voltage will measure ignition voltage. If signal circuit is shorted to ground, voltage will not be present.
    NOTE: Cruise connector is present on vehicles not equipped with cruise control (except SL models without provisions for dealer installed A/C or ABS).
    NOTE: When using cruise/cluster tester, disconnect ignition module electrical connector to allow tachometer signal to function properly. Cruise/cluster tester will add mileage to vehicle odometer.
  2. Connect Cruise/Cluster Tester (SA9115Z) to cruise connector located on driver's side of Heating Ventilation Air Conditioning (HVAC) module. With engine off, apply a 57-63 MPH (92-102 Km/h) signal to instrument cluster. Gauges should function. If gauges function, but are inaccurate, use a scan tester with engine running. Compare speedometer MPH and tachometer RPM to scan tester readings.
  3. Replace instrument cluster if gauges do not properly function. Recheck function of speedometer and tachometer.