C1252

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1252: Brake Booster Pump Motor on Time Abnormally Long
C1252 - Brake Booster Pump Motor on Time Abnormally Long

DESCRIPTION

The motor relay (semiconductor relay) is built into the master cylinder solenoid and drives the pump motor based on a signal from the skid control ECU.





HINT
The pump motor continues operation for the first 3 minutes, and then starts and stops repeatedly.

INSPECTION PROCEDURE

NOTICE:
When replacing the master cylinder solenoid, perform calibration Programming and Relearning.

HINT
When DTC C1253, C1254, C1256 or C1452 is output together with DTC C1252, inspect and repair the trouble area indicated by DTC C1253, C1254, C1256 or C1452 first.

PROCEDURE

1. CHECK PUMP MOTOR OPERATION

(a) Turn the engine switch off.

(b) Depress the brake pedal more than 40 times.

(c) Turn the engine switch on (IG).

(d) Check how the pump motor operates.

Result





D -- RECONFIRM DTC

C -- READ VALUE USING TECHSTREAM (ACCUMULATOR SENSOR)

B -- REPLACE HYDRAULIC BRAKE BOOSTER ASSEMBLY Removal
A -- Continue to next step.

2. CHECK CONNECTION OF PUMP MOTOR WIRE HARNESS C1251

NG -- RETIGHTEN SCREWS
OK -- Continue to next step.

3. CHECK RESISTANCE OF PUMP MOTOR WIRE HARNESS C1251

NG -- REPLACE BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY Disassembly
OK -- Continue to next step.

4. READ VALUE USING TECHSTREAM (ACCUMULATOR SENSOR)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

ABS/VSC/TRAC





(f) Check the accumulator output value.

Result





C -- REPLACE HYDRAULIC BRAKE BOOSTER ASSEMBLY Removal

B -- REPLACE MASTER CYLINDER SOLENOID Disassembly
A -- Continue to next step.

5. RECONFIRM DTC

(a) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(b) Turn the engine switch off.

(c) Turn the engine switch on (IG).

(d) Wait for more than 5 minutes.

(e) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.

Result





HINT
Reinstall the sensors, reconnect the connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

B -- REPLACE BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY Disassembly

A -- REPLACE HYDRAULIC BRAKE BOOSTER ASSEMBLY Removal