DTC C1425 Open in Stop Light Switch Circuit |
| DTC Code | DTC Detection Condition | Trouble Area |
| C1425 | When IG1 terminal voltage is between 9.5 and 17.4 V, an open stop light switch circuit continues for 3 seconds or more. |
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| 1.READ VALUE USING INTELLIGENT TESTER (STOP LIGHT SWITCH) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Enter the following menus: Chassis / ABS/VSC/TRC / Data List.
| 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.
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| OK | |
| 2.RECONFIRM DTC |
Turn the ignition switch off.
Clear the DTCs (Click here).
Start the engine.
Depress the brake pedal several times to test the stop light circuit.
Check if the same DTC is recorded (Click here).
| Result | Proceed to |
| DTC (C1425) is not output | A |
| DTC (C1425) is output | B |
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| A | ||
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| 3.INSPECT STOP LIGHT SWITCH (POWER SOURCE TERMINAL) |
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Make sure that there is no looseness at the locking part and the connecting part of the connectors.
| *1 | Front view of wire harness connector (to Stop Light Switch) |
Disconnect the A27 stop light switch connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| A27-2 - Body ground | Always | 11 to 14 V |
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| OK | |
| Go to step 5 |
| 4.INSPECT STOP LIGHT SWITCH |
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Measure the resistance according to the value(s) in the table below.
| *1 | Component without harness connected (Stop Light Switch) |
| Tester Connection | Switch Condition | Specified Condition |
| 1 - 2 | Switch pin free | Below 1 Ω |
| 1 - 2 | Switch pin pushed in | 10 kΩ or higher |
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| OK | |
| 5.CHECK HARNESS AND CONNECTOR (STP TERMINAL) |
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Turn the ignition switch off.
| *A | for LHD |
| *B | for RHD |
| *1 | Front view of wire harness connector (to Skid Control ECU) |
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the skid control ECU connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Switch Condition | Specified Condition |
| A16-2 (STP) - Body ground | Stop light switch ON (Brake pedal depressed) | 8 to 14 V |
| A16-2 (STP) - Body ground | Stop light switch OFF (Brake pedal released) | Below 1.5 V |
| Tester Connection | Switch Condition | Specified Condition |
| A17-2 (STP) - Body ground | Stop light switch ON (Brake pedal depressed) | 8 to 14 V |
| A17-2 (STP) - Body ground | Stop light switch OFF (Brake pedal released) | Below 1.5 V |
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| OK | ||
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