C1253

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1253/53: Pump Motor Relay Malfunction
C1253/53 - Pump Motor Relay Malfunction

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.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
When replacing the hydraulic brake booster assembly (master cylinder solenoid), perform zero point calibration Programming and Relearning.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (MOTOR RELAY)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG) and turn the Techstream on.

(c) Start the engine.

(d) Enter the following menus: Chassis / ABS/VSC/TRAC / Active Test.

ABS/VSC/TRAC





(e) Check the operation sound of the motor individually when operating it with the Techstream.

OK:

The operation sound of the motor can be heard.

NG -- INSPECT SKID CONTROL ECU (+BM TERMINAL)
OK -- Continue to next step.

2. RECONFIRM DTC

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

(b) Turn the engine switch off.

(c) Depress the brake pedal more than 20 times.

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

(e) Wait until the pump motor stops.

(f) Depress the brake pedal several times until the pump motor turns on. (Procedure A)

(g) Wait until the pump stops. (Procedure B)

(h) Repeat the above steps (procedure A and B) 3 more times.

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

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

Result





B -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

A -- REPLACE MASTER CYLINDER SOLENOID

3. INSPECT SKID CONTROL ECU (+BM TERMINAL)

(a) Disconnect the A24 and A25 skid control ECU connectors.





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

Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. INSPECT SKID CONTROL ECU (GND TERMINAL)

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





Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. RECONFIRM DTC

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

(b) Turn the engine switch off.

(c) Depress the brake pedal more than 20 times.

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

(e) Wait until the pump motor stops.

(f) Depress the brake pedal several times until the pump motor turns on. (Procedure A)

(g) Wait until the pump stops. (Procedure B)

(h) Repeat the above steps (procedure A and B) 3 more times.

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

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

Result





B -- USE SIMULATION METHOD TO CHECK How To Proceed With Troubleshooting

A -- REPLACE MASTER CYLINDER SOLENOID