Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000025DSL
Model Year Start: 2023 Model: Corolla Prod Date Range: [09/2022 -           ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for HV Model): TERMINALS OF ECU; 2023 - 2025 MY Corolla Corolla HV [09/2022 -        ]

TERMINALS OF ECU

CHECK BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY

(a) Disconnect the A157 electric brake booster (brake booster with master cylinder assembly) connector and measure the voltage or resistance on the wire harness side.

*a

Front view of wire harness connector

(to Electric Brake Booster (Brake Booster with Master Cylinder Assembly))

-

-

HINT:

The voltage cannot be measured with the connector connected to the electric brake booster (brake booster with master cylinder assembly) as the connector is watertight.

Standard:

Terminal No. (Symbol)

Terminal Description

Condition

Specified Condition
*: Differs depending on the vehicle model

A157-1 (CBKP)

Electric brake booster (brake booster with master cylinder assembly) backup power supply input

-

-

A157-2 (CA1H)

CAN communication line 1 (H)

-

-

A157-3

-

-

-

A157-4 (IGR) - Body ground

IGR power source input

Ignition switch ON

11 to 14 V

A157-5 (STP) - Body ground

Stop light switch assembly input

Stop light switch assembly on → off (Brake pedal depressed → released)

11 to 14 V → Below 1.5 V

A157-6 (SKS1)

Relative displacement sensor (brake booster with master cylinder assembly) 1 signal input

-

-

A157-7 (SKS2)

Relative displacement sensor (brake booster with master cylinder assembly) 2 signal input

-

-

A157-8 (CWKP) - Body ground

Brake control power supply assembly operation signal output

Always

11 to 14 V

A157-9 (CA2H)

CAN communication line 2 (H)

-

-

A157-10

-

-

-

A157-11 (+BS) - Body ground

Electric brake booster (Brake booster with master cylinder assembly) power supply input

Always

11 to 14 V

A157-12 (CA1L)

CAN communication line 1 (L)

-

-

A157-13

-

-

-

A157-14

-

-

-

A157-15

-

-

-

A157-16

-

-

-

A157-17 (CTY) - Body ground

Front door courtesy light switch assembly input (for driver side)

Driver door closed → open

11 to 14 V or pulse output (maximum 14 V)* → Below 1 V

A157-18 (CA2L)

CAN communication line 2 (L)

-

-

A157-19 (VSK)

Relative displacement sensor (brake booster with master cylinder assembly) power supply output

-

-

A157-20

-

-

-

A157-21 (CLIN)

Communication line with brake control power supply assembly

-

-

A157-22

-

-

-

A157-23

-

-

-

A157-24

-

-

-

A157-25 (SKG)

Relative displacement sensor (brake booster with master cylinder assembly) ground

-

-

A157-26 (GND) - Body ground

Electric brake booster (Brake booster with master cylinder assembly) ground

1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal

Below 1 Ω

CHECK BRAKE ACTUATOR ASSEMBLY

(a) Disconnect the A51 skid control ECU (brake actuator assembly) connector and measure the voltage or resistance on the wire harness side.

*a

Front view of wire harness connector

(to skid control ECU (Brake Actuator Assembly))

-

-

HINT:

The voltage cannot be measured with the connector connected to the skid control ECU (brake actuator assembly) as the connector is watertight.

Standard

Terminal No. (Symbol)

Terminal Description

Condition

Specified Condition
*1: for Instrument Panel

*2: for Shift Panel

A51-1 (+BM) - Body ground

ABS motor relay power supply input

Always

11 to 14 V

A51-2

-

-

-

A51-3

-

-

-

A51-4 (LBL)

Brake fluid level warning switch (Brake master cylinder reservoir assembly) input

-

-

A51-5 (CANH)

CAN communication line 1 (H)

-

-

A51-6 (SKS1)

Brake pedal stroke sensor 1 signal input

-

-

A51-7 (FL-)

Front speed sensor LH (-) signal input

-

-

A51-8

-

-

-

A51-9

-

-

-

A51-10

-

-

-

A51-11 (CA2H)

CAN communication line 2 (H)

-

-

A51-12

-

-

-

A51-13

-

-

-

A51-14 (GND2) - Body ground

Skid control ECU (brake actuator assembly) ground 2

1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal

Below 1 Ω

A51-15

-

-

-

A51-16

-

-

-

A51-17 (VSK)

Brake pedal stroke sensor assembly power supply output

-

-

A51-18

-

-

-

A51-19 (CANL)

CAN communication line 1 (L)

-

-

A51-20

-

-

-

A51-21 (FR+)

Front wheel speed RH (+) power supply output

-

-

A51-22 (RR+)

Rear wheel speed RH (+) power supply output

-

-

A51-23 (RL-)

Rear wheel speed LH (-) signal input

-

-

A51-24 (FL+)

Front wheel speed LH (+) power supply output

-

-

A51-25 (CA2L)

CAN communication line 2 (L)

-

-

A51-26 (FR-)

Front wheel speed RH (-) signal input

-

-

A51-27 (STPO) - Body ground

Stop light control relay (stop light switch assembly) output

Always

11 to 14 V

A51-28

-

-

-

A51-29 (SKG)

Brake pedal stroke sensor assembly ground

-

-

A51-30 (+BS) - Body ground

ABS solenoid relay power supply

Always

11 to 14 V

A51-31

-

-

-

A51-32

-

-

-

A51-33 (SP1)

Speed sensor signal output for meter

-

-

A51-34

-

-

-

A51-35 (PKB)

Parking brake status output

-

-

A51-36 (IGR) - Body ground

IGR power source input

Ignition switch ON

11 to 14 V

A51-37 (RR-)

Rear speed sensor RH (-) signal input

-

-

A51-38 (CSW) - Body ground

VSC OFF switch input

VSC OFF switch is pushed → released

Below 1 Ω → 10 kΩ or higher*1

Below 50 Ω → 10 kΩ or higher*2

A51-39 (RL+)

Rear speed sensor LH (+) power supply output

-

-

A51-40

-

-

-

A51-41 (STP) - Body ground

Stop light switch assembly signal input

Stop light switch assembly on → off (Brake pedal depressed → released)

11 to 14 V → Below 1.5 V

A51-42 (SKS2)

Brake pedal stroke sensor 2 signal input

-

-

A51-43 (STP2) - Body ground

Stop light signal input

Stop light switch assembly on → off (Brake pedal depressed → released)

11 to 14 V → Below 1.5 V

A51-44 (HZRI) - Body ground

Brake hold switch (electric parking brake switch assembly) input

Brake hold switch (electric parking brake switch assembly) on → off (Pressed → not pressed)

Below 1 Ω → 10 kΩ or higher

A51-45

-

-

-

A51-46 (GND1) - Body ground

Skid control ECU (brake actuator assembly) ground 1

1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal

Below 1 Ω