Toyota Tacoma (2015-2018) Service Manual: Open in Stop Light Switch Circuit (C1425)
DESCRIPTION
The skid control ECU (brake actuator assembly) detects the brake operating conditions through a signal transmitted by the stop light switch.
The skid control ECU incorporates a circuit to detect an open circuit. This DTC is output when an open circuit is detected in the stop light signal input line.
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
|---|---|---|---|
|
C1425 |
Open in Stop Light Switch Circuit |
When voltage at terminal +BS is 9.5 to 17.4 V, open circuit occurs between STP terminal circuits A and B for 0.3 seconds or more. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
When replacing the skid control ECU (brake actuator assembly), perform zero point
calibration and store system information (See page
.gif)
).
PROCEDURE
|
1. |
CHECK STOP LIGHT OPERATION |
(a) Check that all stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.
OK:
|
Condition |
Illumination Condition |
|---|---|
|
Brake pedal depressed |
ON |
|
Brake pedal released |
OFF |
| NG | .gif) |
CHECK STOP LIGHT CIRCUIT |
|
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|
2. |
CHECK HARNESS AND CONNECTOR (STP TERMINAL) |
|
(a) Turn the ignition switch off. |
|
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(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(c) Disconnect the S1 skid control ECU (brake actuator assembly) connector.
(d) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
S1-35 (STP) - Body ground |
Stop light switch assembly on (Brake pedal depressed) |
8 to 14 V |
|
Stop light switch assembly off (Brake pedal released) |
Below 1.5 V |
|
*a |
Front view of wire harness connector (to Skid Control ECU [Brake Actuator Assembly]) |
| NG | |
REPAIR OR REPLACE HARNESS OR CONNECTOR (BRAKE ACTUATOR ASSEMBLY - STOP LIGHT CIRCUIT) |
|
|
3. |
RECONFIRM DTC |
(a) Reconnect the S1 skid control ECU (brake actuator assembly) connector.
(b) Clear the DTCs (See page
).
(c) Turn the ignition switch off.
(d) Start the engine.
(e) Depress the brake pedal several times to test the stop light circuit.
(f) Check if the same DTC is recorded (See page
).
HINT:
If troubleshooting has been carried out according to the Problem Symptoms Table,
refer back to the table and proceed to the next step (See page
).
|
Result |
Proceed to |
|---|---|
|
DTC C1425 is not output |
A |
|
DTC C1425 is output |
B |
| A | |
USE SIMULATION METHOD TO CHECK |
| B | |
REPLACE BRAKE ACTUATOR ASSEMBLY |
Master Cylinder Pressure Sensor Zero Point High Malfunction (C1422)
DESCRIPTION
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
C1422
Master Cylinder Pressure Sensor Zero Point High M ...
Stop Light Switch OFF Stuck Malfunction (C1426)
DESCRIPTION
The skid control ECU (brake actuator assembly) inputs the stop light signal and
brake operation condition. When the brake pedal is depressed and the stop light
switch signal is not in ...
Other materials:
AUTO LSD Indicator Light does not Come ON
DESCRIPTION
The AUTO LSD does not operate even if the VSC OFF switch is pressed under the
following conditions:
The brake system is faulty.
The temperature inside the hydraulic brake booster increases and the
AUTO LSD operation is suspended.
WIRING DIAGRAM
CAUTION / NOTI ...
Fog Light Relay
Inspection
INSPECTION
PROCEDURE
1. INSPECT FOG LIGHT RELAY
(a) Check the resistance.
(1) Using an ohmmeter, measure the resistance between the terminals.
Standard:
Tester Connection
Specified Condition
3-5
10 kΩ or higher
...
On-vehicle Inspection
ON-VEHICLE INSPECTION
PROCEDURE
1. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET
(a) This is a method to specify trouble areas by using a manifold gauge set.
Read the manifold gauge pressure when the following conditions are established.
Test conditions:
Engine has been warmed u ...
