This brake light switch is mounted on the brake-pedal assembly and is used to indicate the status of brake pedal to the HECU. This switch is the normal-open type and is closed when the brake-pedal is pressed. And when the brake-pedal is released, the switch is opened. The HECU uses this as the basic signal to recognize a driver's intention for braking.
The HECU monitors the brake light switch circuit for a normal operation and if it has a open or short circuit, this DTC is set.
Item
Detecting Condition
Possible Cause
DTC Strategy
Monitoring the brake switch signal
Open or short in the brake light switch circuit
Faulty brake light switch
Threshold valve
When there is no change in the brake light switch's signal but the signal of pressure sensor is being increased
When the brake light switch's signal is continuously inputted for more than 4 minutes at above 20 km/h(12.4 MPH)
When there is no change of the brake light switch's signal with a vehicle repeating from the acceleration of above 40 km/h(24.8 MPH) to the deceleration of below 3 km/h(1.8 MPH) several times
Fail-Safe
The SCC(Smart Cruise Control)/ AVH(Automatic Vehicle Hold) functions are inhibited.