Anti-Theft Systems: Operation

When mechanical key turns the Passlock(tm) lock cylinder, data is created by a rotating magnet turning past a stationary Hall Effect sensor. This data signal is sent to BCM. The BCM determines validity of the data within a preset time window, and then sends a coded password to ECM/PCM, which then allows fuel injectors to operate normally.

If data is not read within the preset time window, the Vehicle Theft Deterrent (VTD) system will enter short tamper mode. During this short tamper mode, the vehicle will not operate for 4 seconds and SECURITY indicator light will flash. After 3 consecutive failed time window readings, or if incorrect data is read, the VTD system will enter long tamper mode. During the long tamper mode, fuel injectors are shut off for 10 minutes and SECURITY indicator light will flash. Vehicle may crank and temporarily start during tamper modes, but will soon stall due to fuel shut-off.