Toyota Tacoma (2015-2018) Service Manual: Power Supply Drive Circuit (C1257)
DESCRIPTION
The motor relay (semiconductor relay) is built into the hydraulic brake booster and drives the pump motor based on a signal from the skid control ECU (master cylinder solenoid).
|
DTC No. |
DTC Detecting Condition |
Trouble Areas |
|---|---|---|
|
C1257 |
Open in pump motor input circuit |
Hydraulic brake booster pump motor circuit |
PROCEDURE
|
1. |
CHECK HYDRAULIC BRAKE BOOSTER PUMP MOTOR OPERATION |
(a) Turn the ignition switch to OFF.
(b) Disconnect the actuator connector (S1).
(c) Depress the brake pedal more than 20 times.
(d) Turn the ignition switch to the ON position.
(e) Check the hydraulic brake booster pump motor operation.
OK:
Hydraulic brake booster pump operates.
| NG | .gif) |
REPLACE MASTER CYLINDER SOLENOID |
|
.gif)
|
2. |
RECONFIRM DTC |
(a) Turn the ignition switch to OFF.
(b) Reconnect the actuator connector (S1).
(c) Turn the ignition switch to the ON position.
(d) Clear the DTCs (See page .gif)
).
(e) Check if the same DTCs are recorded.
|
Result |
Proceed to |
|---|---|
|
DTC output |
A |
|
DTC not output |
B |
| A | |
REPLACE MASTER CYLINDER SOLENOID |
| B | |
END |
Accumulator Low Pressure (C1256)
DESCRIPTION
The accumulator pressure sensor is connected to the skid control ECU in the master
cylinder solenoid.
DTC No.
DTC Detecting Condition
Trouble Areas
...
Transfer L4 Position Switch Circuit (C1268)
DESCRIPTION
A-TRAC is activated if wheel skid is detected while the transfer is in the L4
position.
DTC Code
DTC Detecting Condition
Trouble Areas
...
Other materials:
Parts Location
PARTS LOCATION
ILLUSTRATION
*A
for Double Cab
*B
for Access Cab
*C
w/ Back Door Power Window
-
-
*1
NO. 1 BACK PANEL PELAY
*2
NO. 2 BACK PANEL RELAY
...
Registration
REGISTRATION
CAUTION / NOTICE / HINT
HINT:
Register a new recognition code when replacing the door control transmitter
module set sub-assembly or the door control receiver.
Add mode is used to retain the already registered codes while registering
a new recognition code. This m ...
Blind Spot Monitor Master Module Beam Axis Inspection Incomplete (C1ABB)
DESCRIPTION
This DTC is stored when a beam axis inspection has not been performed for the
blind spot monitor sensor LH.
HINT:
This DTC is always stored after replacing a blind spot monitor sensor. The purpose
of this DTC is to ensure that beam axis inspection is performed. Completing the
be ...
