Inspection Procedure

ABS / VSC / TRAC: 

1. Connect Techstream to the DLC3.
2. Turn the ignition switch on (IG).
3. Select the Data List mode on Techstream (See DATA LIST/ACTIVE TEST  ).
   ABS / VSC / TRAC
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Downhill Assist Control SW	Downhill assist control switch / ON or OFF	ON Switch ON OFF Switch OFF	-

4. Using Techstream, check the switch condition on Techstream changes according to downhill assist control switch operation.

OK: The Techstream displays ON or OFF according to downhill assist control switch operation. 

NG:  Go to step  3

OK: Go to next step 

1. Turn the ignition switch off.
2. Perform the sensor check in TEST MODE PROCEDURE .

   OK: All Test Mode DTCs are erased. 

   HINT:

   If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

NG: REPLACE BRAKE ACTUATOR ASSEMBLY  (See REMOVAL  )

OK: CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)  (See DIAGNOSIS SYSTEM 

1. Turn the ignition switch off.
2. Make sure that there is no looseness at the locking part and the connecting part of the connector.
3. Disconnect the downhill assist control switch connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFICATION TABLE
   
   

   Tester Connection	Switch Condition	Specified Condition
   4 (B) - 1 (E)	Switch is pushed in	Below 1 Ω
   4 (B) - 1 (E)	Switch is not pushed in	10 kΩ or higher

   NOTE: Check the downhill assist control switch signal after replacement (See TEST MODE PROCEDURE  ).
   Fig 1: Identifying Downhill Assist Control Switch

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE DOWNHILL ASSIST CONTROL SWITCH  (See REMOVAL  )

OK: Go to next step 

1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
2. Disconnect the skid control ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFICATION TABLE
   
   

   Tester Connection	Condition	Specified Condition
   A24-26 (HDCS) - G2-4 (B)	Always	Below 1 Ω
   A24-26 (HDCS) - Body ground	Always	10 kΩ or higher
   G2-1 (E) - Body ground	Always	Below 1 Ω

   HINT:

   If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (See PROBLEM SYMPTOMS TABLE  ).

   Fig 2: Identifying A24 Skid Control ECU & G2 Downhill Assist Control Switch Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: REPLACE BRAKE ACTUATOR ASSEMBLY  (See REMOVAL  )