Circuit Description

Stoplight switch is normally open. When switch is closed, Throttle Actuator Control (TAC) module senses ignition voltage on brakelight switch signal circuit. DTC will set if TAC module senses voltage on brakelight switch signal circuit when switch should be open.

Condition for setting DTC is when PCM senses this switch is not toggling as compared with other brake switch inputs and condition is present for 20 ACCEL/decel cycles.