C1503

C1503

Component Location:

General Description
The ESC switch is used to temporarily deactivate ESC control.

DTC Description
Trouble code is set when the condition that the level of ESC switch is high is continued for 60 sec.
When the ESC switch failure is set ESC Warning lamp will illuminate and HECU inhibit the ESC control and allow the ABS/EBD control.

DTC Detecting Condition:

Specification:

Schematic Diagram:

Monitor Scantool Data
1. Connect scantool to Data Link Connector (DLC).
2. Ignition "ON" & Engine "OFF".
3. Press the ESC SWITCH.
4. Monitor the "TCS/ESC SWITCH" parameter on the scantool.






5. Whenever the switch is pushed up/down, is the ESC off switch's scantool data changed ON/OFF?

YES
a. Fault is intermittent caused by poor connection in ESC switch line or was repaired and HECU memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO
a. Go to "W/Harness Inspection" procedure.

Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?

YES
a. Repair as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
a. Go to "Signal Circuit Inspection" procedure.

Signal Circuit Inspection
1. Ignition "ON" & Engine "OFF" & ESC Switch"ON".
2. Measure voltage between terminal "27" of the HECU harness connector and chassis ground.

Specification : Approx. B+






3. Is the measured voltage within specifications?

YES
a. Fault is intermittent caused by poor connection in esp switch line or was repaired and HECU memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.

NO
a. Check for damaged harness and poor connection in the power harness between the battery terminal (+) and the terminal "27" of the HECU harness connector. Check for open or blown 10 A fuse referring to "Circuit Diagram". Repair as necessary and then go to "Verification of vehicle Repair" procedure.
b. If OK, Go to "Component Inspection" Procedure.

Component Inspection
1. Ignition "OFF".
2. Disconnect ESC switch connector.
3. Measure resistance between terminal "4" of the ESC switch component connector and terminal "5" of the ESC switch component connector.

Specification : Approx. below 1 ohm (In case of pressing the ESC switch)

Approx. Infinite ohms (In case of not pressing the ESC switch)






4. Is the measured resistance within specifications?

YES
a. Fault is intermittent caused by poor connection in ESC switch line or was repaired and HECU memory was not cleared. Go to "Verification of Vehicle Repair" procedure.

NO
a. Substitute with a known-good ESC switch and check for proper operation. If problem is corrected, replace ESC switch and then go to "Verification of Vehicle Repair" procedure.

Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and select "Diagnostic Trouble Codes (DTCs)" mode
2. Using a scantool, Clear DTC.
3. Operate the vehicle within DTC Detecting Condition in General Information.
4. Are any DTCs present?

YES
a. Go to the applicable troubleshooting procedure.

NO
a. System performing to specification at this time.