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:
Utility
UTILITY
NOTICE:
If the forward recognition camera has been replaced due to a malfunction in the
lane departure alert system, be sure to perform Recognition Camera/Target Position
Memory and Optical Axis Learning. Otherwise all systems that use the forward recognition
camera may be affected.
...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT ENGINE COOLANT
(See page )
2. INSPECT ENGINE OIL
(See page )
3. INSPECT BATTERY
(See page )
4. INSPECT SPARK PLUG
(See page )
5. INSPECT AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY
(a) Remove the air cleaner filter element sub-assembly.
(b) Visu ...
Air Conditioning Amplifier Communication Stop Mode
DESCRIPTION
Detection Item
Symptom
Trouble Area
Air Conditioning Amplifier Communication Stop Mode
Either condition is met:
Communication stop for "Air Conditioning Amplifier" is indicated
on the "Commun ...
