DTC C0609-62: Electric Parking Brake Switch Signal Compare Failure [11/2021 - 03/2024]: Procedure

WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.

READ VALUE USING GTS (EPB SWITCH)

Connect the GTS to the DLC3.
Turn the ignition switch to ON.

Enter the following menus: Chassis / Brake/EPB / Data List.

Chassis > Brake/EPB > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
EPB Switch	Electric parking brake switch input	Neutral / Apply / Release / Unknown	Neutral: Lock switch and release switch are off Apply: Lock switch on Release: Release switch on	When not normal, electric parking brake switch release side system may be malfunctioning HINT: EPB stands for electric parking brake.

Chassis > Brake/EPB > Data List

Tester Display
EPB Switch

Operate the electric parking brake switch assembly and check that the value of "EPB Switch" in the Data List changes between Lock and Release in accordance with the operation of the switch.

The value of EPB Switch changes between Lock and Release in accordance with switch operation.

Result

Proceed to
OK
NG

Result:

See step 4

Result:

See step 2

CLEAR DTC

Clear the DTCs.

Chassis > Brake/EPB > Clear DTCs

Result

Proceed to
NEXT

Result:

See step 3

CHECK DTC

Check for DTCs.

Chassis > Brake/EPB > Trouble Codes

Result

Result	Proceed to
DTCs are output	A
DTCs are not output	B

Result:

REPLACE NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to REMOVAL [11/2021 - ]

Result:

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]

INSPECT ELECTRIC PARKING BRAKE SWITCH ASSEMBLY
See step 2

Result

Proceed to

OK

NG

Result:

NG

REPLACE ELECTRIC PARKING BRAKE SWITCH ASSEMBLY. Refer to REMOVAL [11/2021 - ]

Result:

OK

See step 5

CHECK HARNESS AND CONNECTOR (NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) - ELECTRIC PARKING BRAKE SWITCH (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY)

Pre-procedure1

Disconnect the D32 electric parking brake switch (electric parking brake switch assembly) connector.
Disconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
Procedure1

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

Standard Resistance

Tester Connection	Condition	Specified Condition
A38-36 (SWI1) - D32-9 (SWI1)	Always	Below 1 Ω
A38-31 (SWO1) - D32-10 (SWO1)	Always	Below 1 Ω
A38-41 (SWI2) - D32-1 (SWI2)	Always	Below 1 Ω
A38-39 (SWO2) - D32-2 (SWO2)	Always	Below 1 Ω
A38-36 (SWI1) or D32-9 (SWI1) - Body ground	Always	10 kΩ or higher
A38-31 (SWO1) or D32-10 (SWO1) - Body ground	Always	10 kΩ or higher
A38-41 (SWI2) or D32-1 (SWI2) - Body ground	Always	10 kΩ or higher
A38-39 (SWO2) or D32-2 (SWO2) - Body ground	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Post-procedure1

None

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 6

CLEAR DTC

Pre-procedure1

None
Procedure1

Clear the DTCs.

Chassis > Brake/EPB > Clear DTCs

Result

Proceed to
NEXT

Post-procedure1

Turn the ignition switch off.

Result:

See step 7

CHECK DTC

Check for DTCs.

Chassis > Brake/EPB > Trouble Codes

Result

Result	Proceed to
DTCs are output	A
DTCs are not output	B

Result:

REPLACE NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to REMOVAL [11/2021 - ]

Result:

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]