The brake switch has 2 contacts. One allows the stop lights to be supplied and the other is used for finding fault and the correlation between the accelerator pedal position and the brake pedal position.
Also, the brake switch has the cancellation of cruise control.
The ECM senses the state of brake operating through brake switch. The redundant brake circuit is actuated when the accel pedal is depressed and the brake pedal depressed.
The ECM will apply a fail safe mode limiting the signal from the accelerator and controlling the injector operation allowing the engine to 1200 rpm only when the brake is released, APS signal is returned and injector operation re-instated.
If the brake switch 1 and 2 signal is not geneated normally, the ECM judged this as a fault and DTC is set.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Signal check | ● Open in brake switch 1 & 2 circuit ● Short in brake switch 1 & 2 circuit ● Open or short in power circuit ● Fuse blown ● Faulty brake switch ● Faulty ECM |
Enable Conditions | ● Ignition on | |
Threshold Value | ● Case 1: brake switch 1 signal and brake switch 2 signal are abnormally correlated after the ignition switch on. ● Case 2: brake switch 1 signal and brake switch 2 signal are abnormally correlated during the driving | |
Diagnostic Time | ● Case 1: 2 sec ● Case 2: 180 sec | |
MIL Fuel Limit Fuel Cut EGR Off | ● No ● No ● No ● No | |
Fail safe | ● Clutch error monitoring deactivited ● Cruise control system and error monitoring deactivited ● Idle compensation deactivited in case of the lack of battery voltage |
