Vehicle Speed Signal Check for Display Control Unit

WARNING: This page is about a different car, the 2005 Infiniti FX45 and 2005 Infiniti FX35. However, it is still accessible from the selected car via links, so may be relevant.

VEHICLE SPEED OPERATION CHECK
Is speedometer operated normally?

YES or NO
1. YES : GO TO 2.
2. NO : Check combination meter trouble diagnosis. Refer to "TROUBLE DIAGNOSIS ".
CHECK HARNESS
1. Turn ignition switch OFF.
2. Disconnect display control unit connector and unified meter and A/C amp. connector.
3. Check continuity between display control unit harness connector M75 terminal 16 (R/G) and unified meter and A/C amp. harness connector M56 terminal 26 (R/G).
  1. Continuity should exist.
4. Check continuity between display control unit harness connector M75 terminal 16 (R/G) and ground.
  1. Continuity should not exist.
Fig 1: Checking Continuity Between Display Control Unit Harness Connector M75 Terminal 16 (R/G) And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK : GO TO 3.
2. NG : Repair harness or connector.
CHECK VEHICLE SPEED SIGNAL
1. Connect display control unit connector and unified meter and A/C amp. connector.
2. Start the engine.
3. Drive vehicle at a constant speed.
4. Check signal between display control unit harness connector M75 terminal 16 (R/G) and ground with CONSULT-II or oscilloscope.
  1. 16 (R/G) - Ground : Refer to " TERMINALS AND REFERENCE VALUE FOR DISPLAY CONTROL UNIT ".
Fig 2: Connecting Display Control Unit Connector And Unified Meter And A/C Amp
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK : Replace display control unit.
2. NG : Check unified meter and A/C amp. system. Refer to "VEHICLE SPEED SIGNAL INSPECTION ".