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:
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE
If a normal code is displayed during the DTC check but the problem still occurs,
check the circuits for each problem symptom in the order given in the table below
and proceed to the relevant troubleshooting page.
NOTICE:
When replacing the skid control ECU (master cylin ...
Open in One Side of Bus 3 Branch Line
DESCRIPTION
When the CAN bus main lines are normal (no open, short to ground, short to +B
or short between lines) and there is an ECU or sensor on the "Communication Bus
Check" screen that is indicated as not communicating or whose connection status
on the "Communication Bus Ch ...
Removal
REMOVAL
PROCEDURE
1. REMOVE ROOF HEADLINING ASSEMBLY (for LED Type Stop Light)
for Double Cab:
(See page
)
for Access Cab:
(See page
)
2. REMOVE CENTER STOP LIGHT ASSEMBLY (for Bulb Type Stop Light)
(a) Apply protective tape around the center stop light as ...
