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:

Power Source Circuit
DESCRIPTION This circuit provides power to operate the forward recognition camera. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following inspection procedure. PROCEDURE 1. CHECK HARNESS A ...

Engine Switch Illumination Circuit
DESCRIPTION The illuminated entry system controls the engine switch illumination. WIRING DIAGRAM PROCEDURE 1. READ VALUE USING TECHSTREAM (POWER/ENGINE SW LIGHT) (a) Connect the Techstream to the DLC3. (b) Turn the engine switch to ON. (c) Turn the Techstream ...

Multi-terrain Select Indicator Light does not Come ON
DESCRIPTION When the transfer gear position is L4, the multi-terrain select indicator light illuminates and control begins. Under any of the following conditions, the multi-terrain select system does not begin control and the multi-terrain select indicator light does not illuminate. Th ...

© 2011-2025 Copyright www.ttguide.net