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.
Audio Communication Line Check (Between Display Control Unit and Audio Unit).
- CHECK POWER SUPPLY AND GROUND CIRCUIT
- Check system of power supply circuit audio unit. Refer to "POWER SUPPLY CIRCUIT INSPECTION ".
OK or NG
- OK: GO TO 2.
- NG: Check the malfunctioning parts.
- CHECK HARNESS
- Turn ignition switch OFF.
- Disconnect audio unit connector and display control unit connector.
- Check continuity between audio unit and display control unit.CONTINUITY CHECK CHART
Terminals Continuity Display control unit Audio unit Connector Terminal (Wire color) Connector Terminal (Wire color) M43 40 (R/G) M46 23 (R/G) Yes 42 (R/Y) 21 (R/Y) - Check continuity between display control unit and ground.CONTINUITY CHECK CHART
Terminals Continuity Display control unit Ground Connector Terminal (Wire color) M43 40 (R/G) No 42 (R/Y)
OK or NG
- OK: GO TO 3.
- NG: Repair harness or connector.
- CHECK1: AUDIO TX COMMUNICATION SIGNAL
- Connect audio unit connector.
- Turn ignition switch ON.
- Check voltage between audio unit harness connector M46 terminal 23 (R/G) and ground.
Approx. 4V
OK or NG
- OK: GO TO 4.
- NG: Replace audio unit.
- CHECK2: AUDIO RX COMMUNICATION SIGNAL
- Turn ignition switch OFF.
- Disconnect audio unit connector, and connect display control unit connector.
- Turn ignition switch ON.
- Check voltage between display control unit harness connector M43 terminal 42 (R/Y) and ground.
Approx. 4V
OK or NG
- OK: GO TO 5.
- NG: Replace display control unit.
- CHECK3: AUDIO TX COMMUNICATION SIGNAL
- Turn ignition switch OFF.
- Connect audio unit connector.
- Turn ignition switch ON.
- Check signal between display control unit harness connector M43 terminal 40 (R/G) and ground with CONSULT-II or oscilloscope.
40 (R/G) - Ground: Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT ".
OK or NG
- OK: GO TO 6.
- NG: Replace display control unit.
- CHECK4: AUDIO RX COMMUNICATION SIGNAL
- Turn ignition switch ON.
- Check signal between display control unit harness connector "M43" terminal 42 (R/Y) and ground with CONSULT-II or oscilloscope.
42 (R/Y) - Ground: Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT ".
OK or NG
Courtesy of NISSAN MOTOR CO., U.S.A.
- OK: GO TO 7.
- NG: Replace audio unit.
- CHECK SELF-DIAGNOSIS OF DCU
- Turn ignition switch OFF.
- Replace display control unit.
- Turn ignition switch ON.
- Start self-diagnosis of DCU, and check the self-diagnosis result.
OK or NG
- OK: INSPECTION END.
- NG: Replace audio unit.
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.
