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:

Drive Belt
Components COMPONENTS ILLUSTRATION Precaution PRECAUTION NOTICE: Do not apply or add oil or grease to the belt tensioner to prevent abnormal noises from the belt tensioner pulley, belt squealing, etc. Do not allow oil or grease to adhere to the moving parts of the belt ...

Disassembly
DISASSEMBLY CAUTION / NOTICE / HINT HINT: Use the same procedure for both the LH and RH sides. The procedure described below is for the LH side. PROCEDURE 1. REMOVE FOG LIGHT BULB (a) Turn the fog light bulb in the direction indicated by the arrow in the illust ...

Removal
REMOVAL CAUTION / NOTICE / HINT HINT: Use the same procedure for both the RH and LH sides. The procedure described below is for the LH side. PROCEDURE 1. PRECAUTION CAUTION: Be sure to read Precaution thoroughly before servicing (See page ). NOTICE: After turning the ign ...

© 2011-2023 Copyright www.ttguide.net