Circuit Description

The Vehicle Theft Deterrent (VTD) module produces the theft deterrent fuel enable signal when ignition is on and proper key resistor pellet is detected. The PCM monitors fuel enable signal during crank. If proper signal is present on Class II serial data circuit, PCM enables fuel delivery in order to allow engine to start. If PCM is replaced, replacement PCM should learn the password within a few seconds after ignition is turned on. DTC P1630 is an information code indicating that PCM is ready to learn the theft deterrent password. The engine starts and continues to run DTC P1630 set. The PCM remains in theft deterrent password learn mode for more than 2 seconds.