Lexus NX: Short Circuit in Power Source Circuit (C13A1)

Lexus NX Service Manual / Brake / Parking Brake / Electric Parking Brake System / Short Circuit in Power Source Circuit (C13A1)

DESCRIPTION

The following DTCs are stored when a malfunction occurs in the parking brake ECU assembly.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

Note

C13A1

Short Circuit in Power Source Circuit

Both of following conditions are met:

  • Power switch on (IG) or electric parking brake switch (integration control and panel assembly) pulled to lock side with power switch off.
  • Parking brake ECU assembly power source relay is shorted for approx. 60 sec.
  • Wire harness or connector
  • Electric parking brake switch (Integration control and panel assembly)
  • Parking brake ECU assembly

Yes

An electric parking brake system malfunction is displayed on the multi-information display.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.
  • Before disconnecting connectors or fuses, turn the power switch off and wait 20 seconds or more.
  • When replacing the parking brake ECU assembly, operate the electric parking brake switch (integration control and panel assembly), as the parking brake indicator light (red) blinks when the power switch is first turned on (IG).

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (PARKING BRAKE ECU ASSEMBLY - IG POWER SOURCE CIRCUIT)

(a) Turn the power switch off.

*a

Front view of wire harness connector

(to Parking Brake ECU Assembly)

(b) Disconnect the parking brake ECU assembly connector.

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

Q24-5(IG) - Body ground

Power switch off

Below 2.5 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

2.

INSPECT ELECTRIC PARKING BRAKE SWITCH (INTEGRATION CONTROL AND PANEL ASSEMBLY)

(a) Remove the electric parking brake switch (integration control and panel assembly).

Click here

(b) Inspect the electric parking brake switch (integration control and panel assembly).

Click here

NG

REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY

OK

3.

CHECK HARNESS AND CONNECTOR (PARKING BRAKE ECU ASSEMBLY - ELECTRIC PARKING BRAKE SWITCH (INTEGRATION CONTROL AND PANEL ASSEMBLY))

(a) Disconnect the I35 electric parking brake switch (integration control and panel assembly) connector.

(b) Disconnect the parking brake ECU assembly connector.

*a

Front view of wire harness connector

(to Parking Brake ECU Assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Q24-20 (LCK1) - Body ground

Always

10 kΩ or higher

Q24-15 (LCK2) - Body ground

Always

10 kΩ or higher

Q24-16 (REL2) - Body ground

Always

10 kΩ or higher

Q24-19 (REL1) - Body ground

Always

10 kΩ or higher

OK

REPLACE PARKING BRAKE ECU ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

READ NEXT:

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DESCRIPTION When the power switch is turned on (IG), power is supplied to the parking brake ECU assembly. This DTC is stored if the IG power source is not input to the parking brake ECU assembly when

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DESCRIPTION When the electric parking brake switch (integration control and panel assembly) is pulled to the lock side, a lock request signal is output to the parking brake ECU assembly. DTC No.

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DESCRIPTION When the electric parking brake switch (integration control and panel assembly) is pushed to the release side, a release request signal is output to the parking brake ECU assembly. DTC

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