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
   
   

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

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

(REFERENCE) INSPECTION USING OSCILLOSCOPE 

Fig 1: Identifying Combination Meter Terminal (Tacho)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Check the input signal waveform.
   1. Remove the combination meter assy with connectors still connected.
   2. Connect the oscilloscope to the terminals C11-27 of combination meter assy and body ground.
   3. Start engine.
   4. Check the signal waveform.
   ITEM AND CONTENTS
   
   

   Item	Contents
   Tool setting	10 V/DIV, 20 ms/DV
   Vehicle Condition	Engine Idle Speed

   Fig 2: Signal Waveform Graph

   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 C11-27 of combination meter connector.

   Standard: There is continuity. 

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