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
HINT:
Remove the hydraulic brake booster before the inspection (See page
).
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
hydraulic brake booster and brake booster pump (See page
).
Torque:
2.9 N·m {30 kgf·cm, 26 in·lbf}
NG | ![]() |
RETIGHTEN SCREWS |
|
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 |
|
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.
Result |
Proceed to |
---|---|
DTC output |
A |
DTC not output |
B |
A | ![]() |
REPLACE MASTER CYLINDER SOLENOID |
B | ![]() |
END |
Theft Deterrent System Unexpectedly Sets Itself
DESCRIPTION
A situation in which the theft deterrent system unexpectedly sets itself can
be caused when the main body ECU (multiplex network body ECU) cannot detect whether
a door is open or closed.
If the theft deterrent system unexpectedly sets itself, there may be a malfunction
in a court ...
Side Airbag Sensor RH Circuit Malfunction (B1620/21)
DESCRIPTION
The side airbag sensor assembly RH consists of parts such as the safing sensor,
the diagnostic circuit and the lateral deceleration sensor.
When the airbag sensor assembly receives signals from the lateral deceleration
sensor, it determines whether or not the SRS should be activate ...
Data List / Active Test
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
Using the Techstream to read the Data List allows values or states of switches,
sensors, actuators and other items to be read without removing any parts. This non-intrusive
inspection can be very useful because intermittent conditions or signals may ...