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:
ACC Signal Circuit
DESCRIPTION
This circuit detects whether the ignition switch is ACC or off, and sends this
information to the main body ECU (multiplex network body ECU).
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing
the fo ...
Inspection
INSPECTION
PROCEDURE
1. INSPECT REAR AXLE SHAFT
(a) Using a dial indicator, measure the runout of the shaft and flange.
Maximum runout:
Shaft runout: 1.5 mm (0.0591 in.)
Flange runout: 0.05 mm (0.0020 in.)
If the rear axle shaft or flange is damaged or worn, or the runout is greater
than ...
Steering Angle Sensor Unusual Bank Angle Detected (C1440)
DESCRIPTION
If the skid control ECU (master cylinder solenoid) determines that the vehicle
is being driven at a steep bank angle, the skid control ECU (master cylinder solenoid)
stores DTC C1440 while VSC operation is temporarily disabled. It is not a malfunction
if the system and sensor circ ...
