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Speedometer/Vehicle Speed (4-Pulse) Signal

  1. Drive vehicle and check odometer operation. If odometer does not operate, trouble shoot odometer. If odometer operates properly, remove instrument cluster with wiring harness still attached and go to next step.
  2. Turn ignition on. Connect voltmeter between instrument cluster terminal No. 10 (connector "A") and ground. See Fig 1. Jack up front of vehicle and rotate drive shaft.
  3. Voltage should fluctuate between zero volts to 5 volts (or more) per revolution of drive shaft. If voltage does not exist or does not fluctuate as indicated, check instrument cluster power source. If voltage fluctuates, check wiring harness between instrument cluster and cruise control ECU.
  4. If speedometer/vehicle speed (4-pulse) signal and wiring harness are okay, check and replace cruise control ECU. If speedometer/vehicle speed (4-pulse) signal and wiring harness are not okay, trouble shoot instrument cluster or repair wiring harness.
Fig 1: Identifying Cruise Control System Connectors
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