A-TRAC Indicator Light Remains ON

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: A-TRAC Indicator Light Remains ON
- A-TRAC Indicator Light Remains ON

DESCRIPTION

This is the A-TRAC main switch circuit. When the A-TRAC switch is turned on with the transfer in L4, the A-TRAC function is available and the A-TRAC indicator light illuminates.

WIRING DIAGRAM





INSPECTION PROCEDURE

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

PROCEDURE

1. CHECK CAN COMMUNICATION LINE

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Select CAN Bus Check from the System Selection Menu screen and follow the prompts on the screen to inspect the CAN bus Diagnosis System.

OK:

CAN Bus Check indicates no malfunctions in CAN communication.

NG -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) Initial Inspection and Diagnostic Overview
OK -- Continue to next step.

2. INSPECT TRACTION CONTROL SWITCH (A-TRAC SWITCH)

(a) Remove the A-TRAC switch Removal.

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





Standard Resistance:





Text in Illustration





NG -- REPLACE TRACTION CONTROL SWITCH (A-TRAC SWITCH) Removal
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - A-TRAC SWITCH)

(a) Disconnect the A6 skid control ECU connector.

(b) Disconnect the U3 A-TRAC 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.

4. READ VALUE USING TECHSTREAM (A-TRAC INDICATOR LIGHT)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

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

(f) Check the condition of the A-TRAC switch by operating the Techstream.

ABS/VSC/TRAC





OK:

The Techstream displays ON or OFF according to A-TRAC switch operation.

NG -- REPLACE MASTER CYLINDER SOLENOID Disassembly

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