Vehicle Speed Signal Inspection

Symptom: Speedometer or odo/trip meter indication is malfunction.

1. CHECK UNIFIED METER AND A/C AMP. INPUT SIGNAL 
   1. Connect CONSULT-II, and start engine.
   2. Compare the value in "SPEED METER" of "DATA MONITOR" in "METER A/C AMP" to that in speedometer in the combination meter during driving.

      Is the value in speedometer almost same as that in the monitor? 

      YES: Preform self-diagnosis of ABS actuator and electric unit (control unit). Refer to "CONSULT-II FUNCTIONS (ABS) ".

      NO: GO TO 2.

   Fig 1: CONSULT-II Display - Data Meter

   Courtesy of NISSAN MOTOR CO., U.S.A.
2. CHECK UNIFIED METER AND A/C AMP. OUTPUT SIGNAL 
   1. Start engine and drive vehicle at approximately 40 km/h (25 MPH).
   2. Check voltage signal between unified meter and A/C amp. harness connector and ground.
   UNIFIED METER AND A/C AMP. OUTPUT SIGNAL
   
   

   Terminals			Voltage (Approx.)
   (+)		(-)
   Unified meter and A/C amp.connector	Terminal
   M64	28	Ground

   Fig 2: Checking Voltage Signal Between Unified Meter And A/C Amp. Harness Connector And Ground

   Courtesy of NISSAN MOTOR CO., U.S.A.
   NOTE: Maximum voltage may be 5 V due to specifications (connected units).

   OK or NG 

   OK: GO TO 3.

   NG-1: If monitor indicates "0 V" constantly, perform the following.

   1. Check each unit inputting vehicle speed signal (8 pulse). Malfunction is caused by short circuit between each unit and unified meter and A/C amp.
   2. Repair or replace malfunctioning parts.

   NG-2: If monitor indicates "5 V" or "12 V" constantly, replace unified meter and A/C amp.

3. CHECK CONTINUITY BETWEEN COMBINATION METER AND UNIFIED METER AND A/C AMP. 
   1. Turn ignition switch OFF.
   2. Disconnect combination meter connector and unified meter and A/C amp. connector.
   3. Check continuity between combination meter harness connector (A) and unified meter and A/C amp. harness connector (B).
   CONNECTOR TERMINALS SPECIFICATIONS
   
   

   A		B		Continuity
   Connector	Terminal	Connector	Terminal
   M52	1	M64	28	Yes

   Fig 3: Checking Continuity Between Combination Meter Harness Connector And Unified Meter And A/C Amp. Harness Connector

   Courtesy of NISSAN MOTOR CO., U.S.A.

   OK or NG 

   OK: Replace combination meter.

   NG: Repair harness or connector.