C1283
BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1268, C1283: Transfer L4 Position Switch Circuit
C1283 - L4 Position Switch
DESCRIPTION
A-TRAC is activated if wheel skid is detected while the transfer is in the L4(for automatic transmission) or LL(for manual transmission) position.
* *1: for 4WD
* *2: for 2WD
* *3: w/ Rear Differential Lock
* *4: w/o Rear Differential Lock
* *5: for Manual Transmission
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the master cylinder solenoid, perform zero point calibration Calibration.
HINT
The Skid Control ECU uses the NEO terminal to determine whether the vehicle is 2WD or 4WD.
PROCEDURE
1. CHECK VEHICLE EQUIPMENT
(a) Confirm whether the vehicle is 2WD or 4WD.
Result
B -- INSPECT SKID CONTROL ECU (NEO TERMINAL)
A -- Continue to next step.
2. CHECK CONNECTOR CONNECTION CONDITION
(a) Disconnect the A4 skid control ECU connector.
(b) Confirm that the connector's contacts are not contaminated by foreign substances or water seepage.
OK:
Connector's contacts are not contaminated by foreign substances or water seepage.
NG -- CLEAN CONNECTOR
OK -- Continue to next step.
3. INSPECT SKID CONTROL ECU (NEO TERMINAL)
(a) Disconnect the A4 skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MASTER CYLINDER SOLENOID Disassembly
4. INSPECT SKID CONTROL ECU (NEO TERMINAL)
(a) Disconnect the A4 skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
5. INSPECT SKID CONTROL ECU (EXI TERMINAL VOLTAGE)
(a) for Automatic Transmission
(1) Disconnect the A4 skid control ECU connector.
(2) Turn the ignition switch to ON.
(3) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
(b) for Manual Transmission
(1) Disconnect the A4 skid control ECU connector.
(2) Turn the ignition switch to ON.
(3) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
Result
D -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - 4WD CONTROL ECU (REAR DIFF LOCK))
C -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ECM)
B -- CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ECM, 4WD CONTROL ECU (REAR DIFF LOCK))
A -- Continue to next step.
6. RECONFIRM DTC
(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result
B -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting
A -- REPLACE MASTER CYLINDER SOLENOID Disassembly
7. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ECM, 4WD CONTROL ECU (REAR DIFF LOCK))
(a) Disconnect the A4 skid control ECU connector.
(b) Disconnect the transfer indicator switch (for L4 position) connector.
(c) Disconnect the ECM connector.
(d) Disconnect the four wheel drive control ECU connector.
(e) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Result
B -- REPLACE 4 WHEEL DRIVE CONTROL ECU NO.2
A -- REPAIR OR REPLACE HARNESS OR CONNECTOR
8. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - ECM)
(a) Disconnect the A4 skid control ECU connector.
(b) Disconnect the transfer indicator switch (for L4 position) connector.
(c) Disconnect the ECM connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Result
B -- REPLACE ECM
A -- REPAIR OR REPLACE HARNESS OR CONNECTOR
9. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - 4WD CONTROL ECU (REAR DIFF LOCK))
(a) Disconnect the A4 skid control ECU connector.
(b) Disconnect the transfer indicator switch (for LL position) connector.
(c) Disconnect the four wheel drive control ECU connector.
(d) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Result
B -- REPLACE 4 WHEEL DRIVE CONTROL ECU NO.2
A -- REPAIR OR REPLACE HARNESS OR CONNECTOR
10. REPLACE 4 WHEEL DRIVE CONTROL ECU NO.2
(a) Replace the four wheel drive control ECU.
(b) Clear the DTCs.
(c) Turn the ignition switch off.
(d) Check if the same DTC is output.
Result
B -- REPLACE ECM
A -- END
11. REPLACE ECM
(a) Replace the ECM Removal.
(b) Clear the DTCs.
(c) Turn the ignition switch off.
(d) Check if the same DTC is output.
Result
B -- REPLACE MASTER CYLINDER SOLENOID Disassembly
A -- END