C1254

BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1254/54: Pressure Switch Circuit



DESCRIPTION

The accumulator pressure sensor is connected to the skid control ECU in the master cylinder solenoid.




HINT: If the code (C1254/54) is output, the following conditions will occur:
- The ABS, VSC TRAC, and BRAKE warning lights and SLIP and VSC OFF indicator lights will come on.
- The skid control buzzer sounds.
- Control of all systems other than EBD is canceled.





INSPECTION PROCEDURE
NOTE:
When replacing the master cylinder solenoid, perform zero point calibration Calibration.

PROCEDURE

1. READ VALUE USING TECHSTREAM (ACCUMULATOR PRESSURE SENSOR)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch off.
(c) Depress the brake pedal more than 20 times.
(d) Turn the ignition switch to the ON position and push Techstream main switch ON.
(e) Select "Data List" mode on Techstream.

ABS/VSC/TRAC





(f) Check the accumulator output value.
Result:






B -- REPLACE MASTER CYLINDER SOLENOID
A -- Continue to next step.
2. READ VALUE USING TECHSTREAM (MASTER CYLINDER PRESSURE SENSOR)
(a) Turn the ignition switch off.
(b) Depress the brake pedal more than 20 times.
(c) Install the brake pedal effort gauge (SST), and bleed air.
SST: 09709-29018
(d) Turn the ignition switch to the ON position and push Techstream main switch ON.
(e) Select "Data List" mode on Techstream.

ABS/VSC/TRAC





(f) Check that the master cylinder pressure sensor's output value is normal.
OK:
Master cylinder pressure sensor value is normal.
NG -- REPLACE MASTER CYLINDER SOLENOID
OK -- Continue to next step.
3. RECONFIRM DTC
(a) Clear the DTC Reading and Clearing Diagnostic Trouble Codes.
(b) Turn the ignition switch off.
(c) Depress the brake pedal more than 20 times.
(d) Turn the ignition switch to the ON position.
(e) Wait until the pump motor stops.
(f) Depress the brake pedal and release it.
(g) Wait for 25 minutes.
(h) Check if the same DTC is detected Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- REPLACE MASTER CYLINDER SOLENOID