C1503 TCS/ESC(ESP) Switch error - Automotive Repair Guides & Equipment

COMPONENT LOCATION

GENERAL DESCRIPTION

Driver can inhibit the ESP control by ESP switch.

When switch signal send into HECU, ESP warning lamp go ON and ESP control is stopped and if next switch signal is inputted again, ESP 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 ESP switch is high is continued for 60sec.

When the ESP switch failure is set, Warning lamps won’t illuminate and HECU allow the ABS/EBD/ESP control.

DTC DETECTING CONDITION

Item

Detecting Condition

Possible cause

DTC Strategy

Circuit Monitoring

Open or short ESP switch circuit

Faulty ESP switch

Enable Conditions

When the ESP switch is ON for 1 minute.

Fail Safe

Inhibit the ESP control and allow the ABS/EBD control.

The ESP warning lamp is activated.

SPECIFICATION

Engine ON	ESP switch HIGH	ESP switch LOW
Engine ON	7.0V ~ 16.0V	0V ~ 3.0V

DIAGNOSTIC CIRCUIT DIAGRAM

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.

Has a problem been found?

	▶ Repair as necessary
	▶ Go to “Signal Circuit Inspection” procedure.

SIGNAL CIRCUIT INSPECTION

■ Open or Short Check

1.	Ignition “ON” & Engine “OFF”.

2.	Press the ESP SWITCH.

Measure voltage between ESP switch signal terminal of the HECU harness connector and chassis ground.

Approx B+

Is the measured value within specifications?

	▶ Go to “Component Inspection” Procedure.
	▶ Check for open or blown fuse referring to “Circuit Diagram”. Repair open or short in power circuit between battery and HECU harness connector

COMPONENT INSPECTION

■ ESP switch Check

1.	Ignition “OFF” & Engine “OFF”.

2.	Disconnect the ESP switch connector.

Measure resistance between power terminal and siganl terminal of the ESP switch connector.

Specification : Approx. below 1Ω (In case of pressing the ESP switch)

Approx. ∞ Ω (In case of not pressing the ESP switch)

Is the measured value within specifications?

	▶ Fault is intermittent caused by poor connection in ESP switch harness and/or HECU’s connector. .
	▶ Substitute with a known-good ESP switch and check for proper operation. If problem is corrected, replace ESP switch

New Videos on our YouTube Channel Every Week, Subscribe Now!

Related Posts