Downhill Assist Control Indicator Light does not Come ON

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: Downhill Assist Control Indicator Light does not Come ON
- Downhill Assist Control Indicator Light does not Come ON

DESCRIPTION

Even if the downhill assist control switch is pressed, the downhill assist control indicator light blinks and downhill assist control does not activate under the following conditions:

* The transfer is in H4.

* The brake system is malfunctioning.

* The temperature of the hydraulic brake booster increases and downhill assist control is temporarily canceled.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the master cylinder solenoid, perform calibration Programming and Relearning.

PROCEDURE

1. CHECK CAN COMMUNICATION LINE ABS Warning Light Remains ON

NG -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting
OK -- Continue to next step.

2. CHECK FOR DTC

(a) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.

Result





B -- REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Vehicle Stability Control System
A -- Continue to next step.

3. INSPECT DOWNHILL ASSIST CONTROL SWITCH (COMBINATION SWITCH)

(a) Remove the combination switch Removal.

(b) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





Text in Illustration





NG -- REPLACE COMBINATION SWITCH ASSEMBLY Removal
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU HDCS CIRCUIT)

(a) Disconnect the A7 skid control ECU connector.

(b) Disconnect the i5 combination switch connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. READ VALUE USING TECHSTREAM (DOWNHILL ASSIST CONTROL LIGHT)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

ABS/VSC/TRAC





(f) When performing the Downhill Assist Control Light Active Test, check Downhill Assist Control Light in the Data List Data List / Active Test.

ABS/VSC/TRAC





Result





B -- REPLACE MASTER CYLINDER SOLENOID Disassembly

A -- GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How To Proceed With Troubleshooting