Inspection Procedure

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

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO NEXT STEP 

1. Remove the distance control ECU with connector.
2. Turn the ignition switch ON.
   Fig 1: Inspecting Distance Control ECU Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check the signal waveform between terminal LCS (D2-25) and GND (D2-12) of the distance control ECU.

   Standard: 

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

   HINT:

   • Gauge set: 2 V/DIV, 5 ms/DIV
   • Condition: Ignition switch ON
   Fig 2: Checking Waveform Between Terminal LCS (D2-25) And GND (D2-12)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE DISTANCE CONTROL ECU ASSEMBLY 

OK: REPLACE ECM