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Vehicle Speed Signal Check

WARNING: This page is about a different car, the 2003 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.
  1. VEHICLE SPEED OPERATION CHECK 

    Does speedometer is operated normally?

    Yes or No

    1. YES : GO TO 2.
    2. NO : Check combination meter trouble diagnosis. Refer to DIAGNOSIS FLOW .
  2. HARNESS CHECK 
    1. Turn the ignition switch OFF.
    2. Disconnect audio unit connector and unified meter and A/C amp. connector.
    3. Check continuity between audio unit harness connector M46 terminal 22 (V/W) and unified meter and A/C amp. harness connector M50 terminal 26 (V/W).
      1. Continuity should exist. 
    4. Check continuity between audio unit harness connector M46 terminal 22 (V/W) and ground.
      1. Continuity should not exist. 

    OK or NG

    1. OK : GO TO 3.
    2. NG :
      • Check connector housings for disconnected or loose terminals.
      • Repair harness or connector.
    Fig 1: Checking Continuity Between Audio Unit Harness Connector M46 Terminal 22 And Unified Meter And A/C Amp. Harness Connector M50 Terminal 26, And Between Audio Unit Harness Connector M46 Terminal 22 And Ground
    G03359855Courtesy of NISSAN MOTOR CO., U.S.A.
  3. VEHICLE SPEED SIGNAL CHECK 1 
    1. Connect audio unit connector.
    2. Turn the ignition switch ON.
    3. Check voltage between audio unit harness connector M46 terminal 22 (V/W) and ground.
      1. Approx. 3.5V or more 

    OK or NG

    1. OK : GO TO 4.
    2. NG : Replace audio unit.
    Fig 2: Checking Voltage Between Audio Unit Harness Connector M46 Terminal 22 And Ground
    G03359856Courtesy of NISSAN MOTOR CO., U.S.A.
  4. VEHICLE SPEED SIGNAL CHECK 2 
    1. Connect unified meter and A/C amp. connector.
    2. Start engine and drive vehicle at more than 40 km/h (25 MPH).
    3. Check the signal between audio unit harness connector M46 terminal 22 (V/W) and ground with CONSULT-II or oscilloscope.
    Fig 3: Identifying Audio Unit Harness Connectors Reference Signal Graph
    G03359857Courtesy of NISSAN MOTOR CO., U.S.A.
    Fig 4: Checking Signal Between Audio Unit Harness Connector M46 Terminal And Ground
    G03359858Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK : Inspection end.
    2. NG : Replace unified meter and A/C amp.