PASSLOCK™ System

When mechanical key turns Passlock™ lock cylinder, a Resistance Code (R-Code), is created by a rotating magnet turning past a stationary Hall Effect sensor. R-Code is sent to the BCM. The BCM determines validity of R-Code within a preset time window, then sends a coded password over the class 2 serial data line to the Powertrain Control Module (PCM)/Vehicle Control Module (VCM), which then allows fuel injectors to operate normally.

If BCM sends a password that is different than learned password in PCM/VCM, the PCM/VCM will enter no start mode. During this mode, fuel injectors are shut off for 10 minutes and SECURITY indicator light will stay on. Engine may crank and temporarily start, but will soon stall due to fuel shut-off. If a large magnet is placed near Passlock™ sensor, a tamper signal will be sent to BCM. The system is continually self diagnosing certain functions. If a malfunction exists, system will store a Diagnostic Trouble Code (DTC). BCM does not illuminate Malfunction Indicator Light (MIL). If a Passlock™ DTC exists, BCM illuminates SECURITY indicator light.