Pump Motor Relay Malfunction - Vehicle Stability Control System

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

DTC 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
NOTE: When replacing the hydraulic brake booster, perform zero point calibration Programming and Relearning.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (ABS MOTOR RELAY)
(a) Connect a Techstream to DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the tester on.
(d) Select the following menu items: Chassis / ABS/VSC/TRAC/ Active Test
Select the "ABS Motor Relay" in the Active Test and operate the actuator motor using the Techstream.

ACTIVE TEST: ABS/VSC/TRAC





(e) Check for operation sound of the actuator motor when it is operated with the Techstream.
OK:
The operation sound of the actuator motor can be heard.
NG -- INSPECT FUSE (ABS MTR)
OK -- Continue to next step.
2. 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 ON.
(e) Wait until the pump motor stops.
(f) Depress the brake pedal several times until the pump motor is turned on.
(g) Wait until the pump stops.
(h) Repeat (f) and (g) three times.
(i) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- REPLACE HYDRAULIC BRAKE BOOSTER
3. INSPECT FUSE (ABS MTR)




(a) Remove the ABS MTR fuse from the engine room R/B No. 2.
(b) Measure the resistance.
Standard resistance:
Below 1 Ohms
NG -- CHECK FOR SHORTS IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE
OK -- Continue to next step.
4. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (+BM, +BM2 TERMINAL)




(a) Disconnect the skid control ECU connectors.
(b) Measure the voltage.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+BM1 AND +BM2 CIRCUIT)
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)




(a) Disconnect the skid control ECU connectors.
(b) Measure the resistance.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK -- Continue to next step.
6. 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 ON.
(e) Wait until the pump motor stops.
(f) Depress the brake pedal several times until the pump motor is turned on.
(g) Wait until the pump stops.
(h) Repeat (f) and (g) three times.
(i) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.
Result:






B -- END
A -- REPLACE HYDRAULIC BRAKE BOOSTER