Toyota Yaris: Vehicle Stability Control System / Brake Master Cylinder Pressure Sensor Supply Voltage Circuit Short to Ground or Open (C122D14)

Toyota Yaris XP210 (2020-2024) Reapir and Service Manual / Brake / Brake Control / Dynamic Control Systems / Vehicle Stability Control System / Brake Master Cylinder Pressure Sensor Supply Voltage Circuit Short to Ground or Open (C122D14)

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from
C122D14	Brake Master Cylinder Pressure Sensor Supply Voltage Circuit Short to Ground or Open	Master cylinder pressure sensor power supply voltage decrease occurs or history of voltage decrease exists, and defective master cylinder pressure sensor output continues for 1.2 seconds or more.	Master cylinder pressure sensor output defective Skid control ECU (brake actuator assembly)	Brake

WIRING DIAGRAM

Refer to DTC C137BA2.

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CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
After replacing the skid control ECU (brake actuator assembly), perform "Calibration".
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PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (+BS TERMINAL)

(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

OK:

The connector is securely connected.

*a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

(b) Disconnect the A108 skid control ECU (brake actuator assembly) connector.

OK:

No deformation or corrosion.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A108-38 (+BS) - Body ground	Always	11 to 14 V
A108-38 (+BS) - A108-25 (GND1)	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

CLEAR DTC

(a) Reconnect the A108 skid control ECU (brake actuator assembly) connector.

(b) Operate the GTS to clear the codes.

Chassis > Brake > Clear DTCs

(d) Turn the ignition switch off.

3.	RECONFIRM DTC

(a) Operate the GTS to read the DTCs.

Chassis > Brake > Trouble Codes

(b) Check if the same DTC is output.

Result	Proceed to
C122D14 is not output	A
C122D14 is output	B

USE SIMULATION METHOD TO CHECK

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