Vehicle Speed Signal Check for NAVI Control Unit

WARNING: This page is about a different car, the 2004 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.

CHECK HARNESS
1. Turn ignition switch OFF.
2. Disconnect NAVI control unit connector, combination meter connector, display control unit connector and shift lock control unit connector.
3. Check continuity between NAVI control unit harness connector B152 terminal 28 (W/R) and combination meter harness connector M24 terminal 29 (W/R).
  Continuity should exist.
4. Check continuity between NAVI control unit harness connector B152 terminal 28 (W/R) and ground.
  Continuity should not exist.
  
  Fig 1: Checking Continuity Between NAVI Control Unit Harness Connector Terminal And Combination Meter Harness Connector Terminal
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK : GO TO 2.
2. NG : Repair harness.
CHECK 1: VEHICLE SPEED SIGNAL
1. Connect NAVI control unit connector.
2. Turn ignition switch ON.
3. Check voltage between NAVI control unit harness connector B152 terminal 28 (W/R) and ground.
  Approx. 3.5V or more
  
  Fig 2: Checking Voltage Between NAVI Control Unit Harness Connector B152 Terminal 28 (W/R) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK : GO TO 3.
2. NG : Replace NAVI control unit. Refer to , "REMOVAL AND INSTALLATION OF NAVI CONTROL UNIT ".
2: VEHICLE SPEED SIGNAL
1. Connect combination meter connector, display control unit connector and shift lock control unit connector.
2. Drive vehicle at a constant speed.
3. Check signal between NAVI control unit harness connector B152 terminal 28 (W/R) and ground with CONSULT-II or oscilloscope.
  28 (W/R)-Ground: Refer to , "TERMINALS AND REFERENCE VALUE FOR NAVI CONTROL UNIT ".
  
  Fig 3: Checking Signal Between NAVI Control Unit Harness Connector B152 Terminal 28 (W/R) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK : Replace NAVI control unit. Refer to , "REMOVAL AND INSTALLATION OF NAVI CONTROL UNIT ".
2. NG : Check combination meter system. Refer to VEHICLE SPEED SIGNAL INSPECTION .