Inspection Procedure

HINT:

Start the inspection from step 1 when using the hand-held tester and start from step 2 when not using the hand-held tester.

1. READ VALUE OF HAND-HELD TESTER (ENGINE SPEED SIGNAL) 
   1. Operate the hand-held tester according to the steps on the display and select "DATA LIST".

   ECM: 

   DATA LIST SPECIFICATION TABLE - ECM
   
   

   Item	Measurement Item/ Range (Display)	Normal Condition	Diagnostic Note
   ENGINE SPD	Engine speed/Min.: 0 rpm, Max.: 16,383 rpm	Almost same as the actual engine speed (When engine is running)	-

   OK: 

   Engine speed displayed on the tester is almost the same as the actual engine speed. 

   NG: GO TO ENGINE CONTROL SYSTEM (See  HOW TO PROCEED WITH TROUBLESHOOTING  (2AZ-FE(PZEV),  HOW TO PROCEED WITH TROUBLESHOOTING  (2AZ-FE),  HOW TO PROCEED WITH TROUBLESHOOTING  (1MZ-FE/3MZ-FE)) 

   OK: Go to Next Step 

2. INSPECT COMBINATION METER ASSY 

   INSPECTION USING OSCILLOSCOPE 

   1. Check the input signal wave form.
      1. Remove the combination meter assy with the connectors still connected.
      2. Connect the oscilloscope to terminal C7-11 and body ground.
      3. Start the engine.
         Fig 1: Identifying Combination Meter Assy Connector Terminal C7-11

         Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
      4. Check the signal wave form according to the condition(s) in the table below.
      Fig 2: Identifying Signal Wave Form Graph
      Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
   COMBINATION METER ASSY - REFERENCE TABLE
   
   

   Item	Condition
   Tool setting	5 V/DIV, 10 ms/DIV
   Vehicle condition	Engine idle speed

   OK: 

   As shown in the illustration 

   NG: Go to step 3 

   OK: REPLACE COMBINATION METER ASSY (SEE  OVERHAUL  ) 

3. CHECK HARNESS OR CONNECTOR (BETWEEN ECM AND COMBINATION METER ASSY) 

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: REPLACE ECM