Inspection Procedure

1. Check output value of ECM.
   1. Connect the hand-held tester to DLC3.
   2. Turn the ignition switch to ON and push the hand-held tester main switch ON.
   3. Select the DATA LIST mode on the hand-held tester.
      DATA LIST DISPLAYING
      
      

      Item	Condition	Specified Condition	Measurement Item/Range (Display)
      ENGINE SPD	With Engine ldling	650-750 RPM	Engine Speed/Min.: 0 RPM, Max.: 16,383 RPM

1. NG: GO TO ENGINE CONTROL SYSTEM 
2. OK: GO to Next step. 

(REFERENCE) INSPECTION USING OSCILLOSCOPE 

1. Check the input signal waveform.
   1. Remove the combination meter assy with connectors still connected.
   Fig 1: Locating Tacho Meter Connector Terminal
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   2. Connect the oscilloscope to the terminals C9-19 of combination meter assy and body ground.
   3. Start engine.
   4. Check the signal waveform.
      WAVEFORM REFERENCE
      
      

      Item	Contents
      Tool setting	10 V/ DIV, 20 ms/ DV
      Vehicle condition	Engine idle speed

      Fig 2: Input Signal Waveform

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. OK: CHECK AND REPLACE COMBINATION METER ASSY 
2. NG: GO to Next step. 

1. Remove the combination meter.
2. Check the continuity between terminals 5 (TACH) of ECM and C9-19 of combination meter connector.

   Standard: There is continuity. 

1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
2. OK: CHECK AND REPLACE ECM