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 Code | DTC Detection Condition | Trouble Area |
---|---|---|
C1251 | There is an open in the motor system circuit (motor input circuit). |
|
INSPECTION PROCEDURE
Note
After replacing the master cylinder solenoid, perform zero point calibration and store the system information Click here.
Tech Tips
Remove the hydraulic brake booster assembly before the inspection (for LHD: Click here, for RHD: Click here.
PROCEDURE
CHECK CONNECTION OF PUMP MOTOR WIRE HARNESS
Remove the hydraulic brake booster assembly (for LHD: Click here, for RHD: Click here.
Check the tightening torque of the 2 screws which secure the wire harness connecting the master cylinder solenoid and brake booster with accumulator pump assembly (for LHD: Click here, for RHD: Click here.
OK |
---|
The harness is tightened to the specified torque. |
NG |
RETIGHTEN SCREWS |
OK |
CHECK RESISTANCE OF PUMP MOTOR WIRE HARNESS
Using a screwdriver, remove the 2 screws and pull out the wire harness from the master cylinder solenoid.
*1 | Pump motor wire harness |
*a | Red wire |
*b | Black wire |
Measure the resistance according to the value(s) in the table below.
Standard Resistance | ||||||
---|---|---|---|---|---|---|
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Tech Tips
Refer to the brake booster with accumulator pump assembly installation procedures:
for LHD Click here
for RHD Click here
NG |
REPLACE BRAKE BOOSTER WITH ACCUMULATOR PUMP ASSEMBLY |
OK |
RECONFIRM DTC
Reassemble the hydraulic brake booster assembly (for LHD: Click here, for RHD: Click here.
Install the hydraulic brake booster assembly (for LHD: Click here, for RHD: Click here.
Clear the DTCs Click here.
Turn the ignition switch off.
Check if the same DTC is output Click here.
Result | Proceed to |
---|---|
DTC is not output | A |
DTC is output (for LHD) | B |
DTC is output (for RHD) | C |
B |
REPLACE MASTER CYLINDER SOLENOID Click here |
C |
REPLACE MASTER CYLINDER SOLENOID Click here |
A |
CHECK FOR INTERMITTENT PROBLEMS Click here