K 2500 Yukon 4WD V8-6.0L VIN U (2000)
VCM), depending on your powertrain option. As a result, the PCM/VCM allows fuel delivery to the engine.
When attempting to start the engine without the proper key in the ignition switch, the Passlock sensor sends an analog voltage signal of a different
value. The BCM compares the preset stored analog voltage value with the signal coming from the sensor. Because both values do not match, the BCM
sends a fuel disable password via the Class 2 serial data link to the PCM/VCM. As a result, the PCM/VCM disables the fuel delivery to the engine and
the vehicle will not start.
CONTENT THEFT DETERRENT (CTD)
The body control module (BCM) monitors several inputs in order to arm and disarm the CTD system and controls the alarm function outputs. When
the BCM detects an unauthorized entry, the BCM applies ground to the horn, the park lamp, and the headlamp relays activating those systems. The
BCM applies ground once per second for approximately 2 minutes, or until a valid input to disarm the system is received by the BCM. When the
CTD system is activated the BCM will also send a message to the security indicator in the instrument cluster via the class 2 serial data link. The BCM
has 8 basic modes for operating the CTD system and 6 discrete inputs to monitor the content theft deterrent system. The CTD system has a remote
panic alarm/vehicle locator feature that can be activated anytime the panic button on the key fob is pressed. When the panic button is pressed the
remote control door lock receiver sends a message to the BCM which will activate the horns and flash the headlamps and parklamps. The remote
panic alarm/vehicle locator activation state can be disabled by the pressing the panic button on the key fob again, or the system will time out after 30
seconds.
POWER REQUIREMENTS
The BCM has 3 main voltage feeds CKT 1140, CKT 39, and CKT 41 and 2 grounds on CKT 1850.
