Toyota Tacoma (2015-2018) Service Manual: IG Supply Voltage Low (C120B)
DESCRIPTION
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
|---|---|---|---|
|
C120B |
IG Supply Voltage Low |
Master cylinder pressure sensor power supply voltage decrease occurs or history of voltage decrease exists, and defective master cylinder pressure sensor output continues for 1 second or more. |
|
WIRING DIAGRAM
Refer to DTC C1417 (See page .gif)
).
CAUTION / NOTICE / HINT
NOTICE:
- When replacing the skid control ECU (brake actuator assembly), perform
zero point calibration and store system information (See page
).
- Inspect the fuses for circuits related to this system before performing the following procedure.
PROCEDURE
|
1. |
CHECK HARNESS AND CONNECTOR (+BS TERMINAL) |
|
(a) Make sure that there is no looseness at the locking part and the connecting part of the connector. |
|
(b) Disconnect the skid control ECU (brake actuator assembly) connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
S1-38 (+BS) - Body ground |
Always |
11 to 14 V |
|
S1-38 (+BS) - S1-25 (GND1) |
Always |
11 to 14 V |
|
*a |
Front view of wire harness connector (to Skid Control ECU [Brake Actuator Assembly]) |
| NG | .gif) |
REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT) |
|
.gif)
|
2. |
RECONFIRM DTC |
(a) Reconnect the S1 skid control ECU (brake actuator assembly) connector.
(b) Clear the DTCs (See page
).
(c) Check if the same DTC is recorded (See page
).
|
Result |
Proceed to |
|---|---|
|
DTC C120B is not output. |
A |
|
DTC C120B is output. |
B |
| A | |
USE SIMULATION METHOD TO CHECK |
| B | |
REPLACE BRAKE ACTUATOR ASSEMBLY |
Control Module Communication Bus OFF (U0073,U0100,U0124,U0126)
DESCRIPTION
The skid control ECU (brake actuator assembly) receives the signals from the
ECM, steering angle sensor (spiral cable with sensor sub-assembly), 4 wheel drive
control ECU*, and yaw ra ...
Zero Point Calibration of Yaw Rate Sensor Undone (C1210,C1336)
DESCRIPTION
The skid control ECU (brake actuator assembly) receives signals from the yaw
rate and acceleration sensor (airbag sensor assembly) via the CAN communication
system.
The airbag sensor ...
Other materials:
Removal
REMOVAL
CAUTION / NOTICE / HINT
NOTICE:
Release the vacuum from booster by depressing the brake pedal several times.
Then remove the brake master cylinder from brake booster.
PROCEDURE
1. PRECAUTION
NOTICE:
After turning the ignition switch off, waiting time may be required before disconnect ...
How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT
HINT:
The vehicle stability control system troubleshooting procedures are
based on the premise that the CAN communication system is functioning normally.
Check the CAN communication system first before troubleshooting the vehicle
stability control system ...
Theft Deterrent System is not Unset when Engine is Running
DESCRIPTION
The theft deterrent system is unset when the IG signal and engine speed signal
are input to the main body ECU (multiplex network body ECU) for 2 seconds or more
continuously.
The engine speed signal is sent from the ECM to the main body ECU (multiplex
network body ECU). For this ...
