The Stop lamp switch is used to judge whether the acceleration system is abnormal or not. The stop lamp switch has a duplex system(signals brake test or brake light) to memorize the abnormality when the signals of depressing and releasing the brake pedal are detected simultaneously.
Checking input signals from brake lamp switch under detecting condition, if the operation state of brake lamp switch does not change for more than 3 sec., PCM sets P0571. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● PCM detects brake lamp input signal when vehicle stops. | ● Poor connection ● Open or short to ground in signal circuit ● Faulty PCM |
Enable Conditions | ● Engine works ● Vehicle speed signal is normal. ● Vehicle speed > 20 kph (during 1sec or more) | |
Threshold value | ● Vehicle speed < 3 kph ● Vehicle acceleration < -6 kph/s ● Brake lamp "OFF" and not changing of brake lamp signal for more 3 sec. | |
Diagnosis Time | ● Continuous | |
MIL On Condition | ● 2 driving cycles |