Inspection Procedure

1. Check for an open or short circuit in harness and connector between the distance control ECU and the laser radar sensor (See HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS ).

NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR 

OK: GO TO NEXT STEP 

1. Remove the distance control ECU with connector.
2. Turn the ignition switch ON.
3. Measure the voltage between terminal IGB (D2-13) of distance control ECU and body ground.

   Standard: 10 to 14 V 

   Fig 1: Inspecting Distance Control ECU Assembly

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4. Check the signal waveform between terminal LRRD (D2-23) of distance control ECU and body ground.

   Standard: 

   The connect signal waveform appears, as shown in  Fig 2  . 

   HINT:

   • Gauge set: 2 V/DIV, 5 ms/DIV
   • Condition: Ignition switch ON

Fig 2: Checking Signal Waveform Between Terminal LRRD (D2-23) And Body Ground

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE DISTANCE CONTROL ECU ASSEMBLY 

OK: REPLACE LASER RADAR SENSOR