Vehicle Speed Signal Check

WARNING: This page is about a different car, the 2004 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.

VEHICLE SPEED OPERATION CHECK
Does speed meter is operated normally?

YES or NO
1. YES: GO TO 2.
2. NO: Check combination meter trouble diagnosis. Refer to METER/GAUGES OPERATION AND ODO/TRIP METER .
HARNESS CHECK
1. Turn the ignition switch OFF.
2. Disconnect NAVI control unit connector and combination meter connector.
3. Check continuity between NAVI control unit harness connector M57 terminal 8 (W/G) and combination meter harness connector M19 terminal 19 (W/G).
  Continuity should exist.
4. Check continuity NAVI control unit harness connector M57 terminal 8(W/G) and ground.
  Continuity should not exist.
  
  Fig 1: Checking Continuity NAVI Control Unit Harness Connector M57 Terminal 8(W/G) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 3.
2. NG :
  - Check harness for open or short between NAVI control unit and combination meter.
  - Check connector housings for disconnected or loose terminals.
VEHICLE SPEED SIGNAL CHECK
1. Connect combination meter connector.
2. Drive vehicle at a constant speed.
3. Check the signal between NAVI control unit harness connector M57 terminal 8 (W/G) and ground with CONSULT-II or oscilloscope.
  8 (W/G) - Ground: Refer to Terminals and Reference Value for NAVI Control unit .
  
  Fig 2: Checking Signal Between NAVI Control Unit Harness Connector M57 Terminal 8 (W/G) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: Replace NAVI control unit.
2. NG: Check combination meter system. Refer to METER/GAUGES OPERATION AND ODO/TRIP METER .