C1503

DTC C1503 TCS/ESC SWITCH ERROR

COMPONENT LOCATION





GENERAL DESCRIPTION
Driver can inhibit the ESC control by ESC switch. When switch signal send into HECU, ESC warning lamp go ON and ESC control is stopped and if next switch signal is inputted again, ESC control is ready. This function is used for sporty driving or vehicle inspection.

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 there is no signal in the warning lamp and HECU inhibit the ESC control and allow the ABS/EBD control.

DTC DETECTING CONDITION





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





5. Whenever the switch is pushed up/down, is the esc off switch's scan tool data changed ON/OFF?

YES
>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
>Go to "W/Harness Inspection" procedure.

TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. 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
>Repair as necessary and then go to "Verification Of Vehicle Repair" procedure.

No
>Go to "Signal Circuit Inspection" procedure.

SIGNAL CIRCUIT INSPECTION
1. Ignition "ON" & Engine "OFF" & ESC Switch "ON".
2. Measure voltage between terminal "31" of the HECU harness connector and chassis ground.





3. Is the measured voltage within specifications?

YES
>Go to "Component Inspection" Procedure.

No
>Check for damaged harness and poor connection in the power harness between the battery terminal(+) and the terminal "31 " 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.
>If OK, Go to "Component Inspection" Procedure.

COMPONENT INSPECTION
1. Ignition "ON".
2. Disconnect ESC switch connector.
3. Press the ESC switch.
4. Measure resistance between terminal "3, 6" of the ESC switch component connector.





5. Is the measured resistance within specifications?

YES
>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
>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
Refer to DTC C1101. C1101