Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Vehicle Speed Signal Check for Display Control Unit
- CHECK VEHICLE SPEED OPERATION
Does speedometer operate normally?
Yes or No
- YES: GO TO 2.
- NO: Check combination meter trouble diagnosis. Refer to "DIAGNOSIS FLOW ".
- CHECK HARNESS
- Turn ignition switch OFF.
- Disconnect display control unit connector, unified meter and A/C amp. connector, NAVI control unit connector, combination meter connector and audio unit connector.
- Check continuity between display control unit harness connector M42 terminal 16 (V/W) and unified meter and A/C amp. harness connector M50 terminal 26 (V/W).
Continuity should exist.
- Check continuity between display control unit harness connector M42 terminal 16 (V/W) and ground.
Continuity should not exist.
OK or NG
- OK: GO TO 3.
- NG: Repair harness.
- CHECK 1: VEHICLE SPEED SIGNAL
- Connect display control unit connector.
- Turn ignition switch ON.
- Check voltage between display control unit harness connector M42 terminal 16 (V/W) and ground.
Approx. 5V
OK or NG
- OK: GO TO 4.
- NG: Replace display control unit.
- CHECK 2: VEHICLE SPEED SIGNAL
- Turn ignition switch OFF.
- Connect unified meter and A/C amp. connector, NAVI control unit connector, combination meter connector and audio unit connector.
- Drive vehicle at a constant speed.
- Check signal between display control unit harness connector M42 terminal 16 (V/W) and ground with CONSULT-II or oscilloscope.
16 (V/W) - Ground: Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT ".
OK or NG
- OK: Replace display control unit.
- NG: Replace unified meter and A/C amp. Refer to "REMOVAL AND INSTALLATION OF UNIFIED METER AND A/C AMP ".
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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