Toyota Tacoma manuals

Toyota Tacoma (2015-2018) Service Manual: Open in Pump Motor Circuit (C1251)

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 (master cylinder solenoid).

DTC No.

DTC Detecting Condition

Trouble Areas

C1251

Open in motor system circuit (motor input circuit)

Hydraulic brake booster pump motor circuit

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION / NOTICE / HINT

HINT:

Remove the hydraulic brake booster before the inspection (See page PROCEDURE ).

PROCEDURE

1.

CHECK BRAKE PUMP MOTOR WIRE HARNESS CONNECTION (MT+ / MT-)

(a) Using a screwdriver, remove the 2 plugs from the hydraulic brake booster (See page (b) Check the tightening torque of 2 screws which fasten the wire harness connecting ).

(b) Check the tightening torque of 2 screws which fasten the wire harness connecting hydraulic brake booster and brake booster pump (See page Torque: ).

Torque:

2.9 N·m {30 kgf·cm, 26 in·lbf}

NG

RETIGHTEN SCREWS

OK

2.

CHECK RESISTANCE OF PUMP MOTOR WIRE HARNESS (MT+/MT-)

(a) Using a screwdriver, remove the 2 screws and pull the wire harness from the hydraulic brake booster.

(b) Measure the resistance between the red wire (MT+) and black wire (MT-).

Resistance:

2 Ω

NG

REPLACE HYDRAULIC BRAKE BOOSTER

OK

3.

RECONFIRM DTC

(a) Reassemble the hydraulic brake booster, then reinstall the hydraulic brake booster.

(b) Clear the DTCs (See page ). (c) Check if the same DTCs are detected. ).

(c) Check if the same DTCs are detected.

Result

Proceed to

DTC output

A

DTC not output

B

A

REPLACE MASTER CYLINDER SOLENOID

B

END

Open Circuit in IG1/IG2 Power Source Circuit (C1242)
DESCRIPTION If there is a problem with the skid control ECU (master cylinder solenoid) power supply circuit, the skid control ECU outputs the DTC and prohibits operation under the fail safe funct ...

Brake Booster Pump Motor on Time Abnormally Long (C1252)
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 (master cylinder solenoid). ...

Other materials:

Inspection
INSPECTION PROCEDURE 1. INSPECT FRONT SHOCK ABSORBER ASSEMBLY (a) Compress and extend the shock absorber rod and check that there is no abnormal resistance or unusual sound during operation. If there is any abnormality, replace the front shock absorber with a new one. NOTICE: When disposin ...

Rear Speed Sensor RH Output Malfunction (C1415,C1416)
DESCRIPTION Refer to DTCs C1403 and C1404 (See page ). DTC No. Detection Item DTC Detection Condition Trouble Area C1415 Rear Speed Sensor RH Output Malfunction Any of the following is detected: An op ...

Operation Check
OPERATION CHECK 1. OPERATION DESCRIPTION (a) Push-button start function: (1) When the electrical key transmitter sub-assembly is in a detection area inside the vehicle and the brake pedal is depressed, the engine is started by pressing the engine switch. (2) When the electrical key transmitt ...

© 2011-2024 Copyright www.ttguide.net