DESCRIPTION
The skid control ECU receives stop light switch signals and uses them to determine whether or not the brakes are applied.
The skid control ECU has a detection circuit that it uses to detect an open in the stop light input line.
If the skid control ECU detects an open in this circuit, it will store this DTC.
DTC No. | DTC Detection Condition | Trouble Area |
---|---|---|
C1425 | An open in the stop light switch input line continues for 3 seconds or more. |
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WIRING DIAGRAM
Refer to DTC C1249 Click here.
INSPECTION PROCEDURE
PROCEDURE
CHECK STOP LIGHT OPERATION
Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal is released.
OK | ||||||
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NG |
INSPECT STOP LIGHT SWITCH ASSEMBLY Click here |
OK |
READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH ASSEMBLY)
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Select the Data List using the intelligent tester Click here.
Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
---|---|---|---|
Stop Light SW | Stop light switch / ON or OFF | ON: Brake pedal depressed OFF: Brake pedal released |
- |
Check that the stop light switch display observed on the intelligent tester changes according to brake pedal operation.
OK |
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The intelligent tester displays on or off according to brake pedal operation. |
NG |
CHECK HARNESS AND CONNECTOR (STP TERMINAL) Click here |
OK |
RECONFIRM DTC
Turn the ignition switch off.
Clear the DTCs Click here.
Turn the ignition switch off.
Start the engine.
Depress the brake pedal several times to test the stop light circuit.
Check if the same DTC is output Click here.
Result | ||||||
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Tech Tips
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.
B |
REPLACE BRAKE ACTUATOR ASSEMBLY Click here |
A |
CHECK FOR INTERMITTENT PROBLEMS Click here
INSPECT STOP LIGHT SWITCH ASSEMBLY
Check the stop light switch assembly Click here.
OK |
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The stop light switch assembly is normal. |
NG |
REPLACE STOP LIGHT SWITCH ASSEMBLY Click here |
OK |
CHECK HARNESS AND CONNECTOR (STP TERMINAL)
*a | Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) |
Reconnect the stop light switch assembly connector.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the skid control ECU connector.
Measure the voltage according to the value(s) in the table below.
Standard Voltage | |||||||||
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Tech Tips
*: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |
OK |
RECONFIRM DTC
Reconnect the skid control ECU connector.
Clear the DTCs Click here.
Turn the ignition switch off.
Start the engine.
Depress the brake pedal several times to test the stop light circuit.
Check if the same DTC is output Click here.
Result | ||||||
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Tech Tips
If the lighting system is normal but the DTC is still output, replace the skid control ECU (brake actuator assembly) Click here.
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.
B |
INSPECT LIGHTING SYSTEM (STOP LIGHT CIRCUIT) Click here |
A |
CHECK FOR INTERMITTENT PROBLEMS Click here
CHECK HARNESS AND CONNECTOR (STP TERMINAL)
*a | Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) |
Turn the ignition switch off.
Make sure that there is no looseness at the locking part and the connecting part of the connector.
Disconnect the skid control ECU connector.
Measure the voltage according to the value(s) in the table below.
Standard Voltage | |||||||||
---|---|---|---|---|---|---|---|---|---|
|
Tech Tips
*: The standard voltage value varies depending on the +BS terminal voltage value. The standard voltage is 85% of the +BS terminal voltage.
Tech Tips
If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts Click here.
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR (STP CIRCUIT) |
OK |
REPLACE BRAKE ACTUATOR ASSEMBLY Click here