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	Mesurement Item /Range (Display)
   COOLANT TEMP	After Warming Up	80 - 95-->°C (176 - 203-->°F)	Coolant Temperature / Min.: -40-->°C, Max.: 140-->°C

   NG: GO TO ENGINE CONTROL SYSTEM 

   OK: GO TO next step 

Fig 1: Identifying Connector Terminal C9-8

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

(REFERENCE) INSPECTION USING OSCILLOSCOPE 

1. Check the input signal waveform.
   1. Remove the combination meter with connectors still connected.
   2. Connect the oscilloscope to the terminals C9-8 of combination meter assy and body ground.
   3. Start engine.
   4. Check the signal waveform.
      SIGNAL WAVEFORM CHECK
      
      

      Item	Contents
      Tool setting	5V/DIV, 100 ms/DV
      Vehicle condition	Ignition switch ON

      Fig 2: Water Temperature Sensor Waveform

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: CHECK AND REPLACE COMBINATION METER ASSY 

      NG: Go to next step 

1. Remove the combination meter.
2. Check the continuity between terminals 14 (THWO) of ECM and C9-8 of combination meter connector.

   Standard: There is continuity. 

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   OK: CHECK AND REPLACE ECM