Vehicle Speed Signal Inspection

WARNING: This page is about a different car, the 2008 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.

CHECK CONTINUITY BETWEEN COMBINATION METER AND UNIFIED METER AND A/C AMP.
1. Disconnect combination meter connector M24 and unified meter and A/C amp. connector M50.
  
  Fig 1: Checking Continuity Between Combination Meter Harness Connector M24 Terminal 20 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
2. Check continuity between combination meter harness connector M24 terminal 20 and unified meter and A/C amp. harness connector M50 terminal 26.
  Continuity should exist.
3. Check continuity between combination meter harness connector M24 terminal 20 and ground.
  Continuity should not exist.
OK or NG

OK: GO TO 2.

NG: Repair harness or connector.
CHECK VOLTAGE OF COMBINATION METER
1. Connect combination meter connector.
2. Turn ignition switch ON.
3. Check voltage between combination meter harness connector M24 terminal 20 and ground.
  
  Fig 2: Checking Voltage Between Combination Meter Connector M24 Terminal 20 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Battery voltage should exist.
OK or NG

OK: GO TO 3.

NG: Replace combination meter, refer to "COMBINATION METER ".
CHECK UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
1. Turn ignition switch OFF.
  
  Fig 3: Checking Voltage Signal Between Combination Meter Harness Connector M24 Terminal 20 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
2. Connect unified meter and A/C amp. connector.
3. Check voltage signal between combination meter harness connector M24 terminal 20 and ground with simple oscilloscope of CONSULT-III.
  20 - Ground:
  
  Fig 4: Identifying Voltage Signal Graph
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK: Replace the combination meter. Refer to "COMBINATION METER ".

NG: GO TO 4.
CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
Perform the ABS actuator and electric unit (control unit) self-diagnosis.
- With traction control but without VDC system, refer to "SELF-DIAGNOSIS ".
OK or NG

OK: Replace the unified meter and A/C amp. Refer to "UNIFIED METER AND A/C AMP. ".

NG: Check the applicable parts.