This switch is mounted on the pedal assembly and is used to send the status of the brake pedal to the HECU.
The switch is turned on when the brake pedal is pressed. The brake light switch is a normally-open contact type which runs to battery voltage when it is active (this means that the brake pedal is pressed). When it is passive (this means that the brake pedal is released), the line is grounded via the brake light bulb.
The brake light signal is a reference to judge driver's intention for braking.
The HECU checks open or short circuit of brake light switch for normal ESP control.
If an error is present, the warning lamp will illuminate.
Item | Detecting Condition | Possible cause |
DTC Strategy |
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Open circuit monitoring | 1. Open circuit in brake switch line 2. Faulty brake light switch 3. Faulty input stage in HECU |
MonitoringPeriod |
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Continuous (only normal voltage) | |
Enable Conditions |
–
In case of over 10kph speed and under 5 bar of Pressure sensor input, monitoring a fault if BLS keeps on for 60s
–
Monitoring a fault if BLS keeps off for 2s 3s in case of over 15 bar of pressure sensor input
–
Monitoring a fault if BLS keeps off for 1s in case of over 50 bar of pressure sensor input | |
Fail Safe |
–
Inhibit the ESP control and allow the ABS/EBD control.
–
The ESP warning lamp is activated. |
Brake Light Switch | Voltage Range of "High" | Voltage Range of "Low" |
7.0V ~ 16.0V | 0V ~ 3V |