1984 Honda Prelude StandardFACTORY OEM SERVICE PROCEDURE

Auto. Trans. Only

  1. Jack up and support the front of vehicle. Push the voltmeter or test light positive probe into the Yellow/Black wire terminal at the control unit connector.
  2. Connect the negative probe to ground. Start engine. Place vehicle in second position (gear selector in 2 position) and accelerate slowly. Battery voltage should be as shown in table.
    SPEED SENSOR VOLTAGE CHECK

    Speed Voltage
    Below 11 MPH Yes
    Above 16 MPH No
  3. If voltmeter readings do not correspond to above MPH ranges, install a new speed sensor and retest. If there was no voltage during step 2), check for bad electrical connection, fuse or faulty speed sensor. Replace or repair as necessary and retest.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.