Test O

Test O1-O3:

Pinpoint Test O: DTC C1408/C1409: Parking Brake Apply/Release Switch Circuit Out Of Range

Normal Operation
The electronic parking brake (EPB) switch circuits 8-CG15 (WH/BU) and 10-CG15 (GY/VT) receive a reference voltage from the EPB module when the switch is in its neutral position. This voltage is between 3.5 and 4.5 volts. When the switch contacts close on the apply or release side, a resistor inside the switch is shorted, causing the voltage on circuits 8-CG15 (WH/BU) or 10 CG15 (GY/VT) to change from 1.5 to 3.0 volts. When the EPB module receives this voltage range on the apply or release circuit, an output signal is generated to the actuator to apply or release the EPB.

Possible Causes
^ EPB switch
^ Circuit 8-CG15 (WH/BU)
^ Circuit 10-CG15 (GY/VT)
^ EPB