OK. I'm reading about the theft deterrent system on this and I learned some things that clear up some of my confusion.
Basically, it has two theft deterrent systems. The CTD and VTD.
The CTD is the Content Theft Deterrent and it does not disable starting. It does utilize the front door modules as an input. It' also will turn on the Security light on the dash with the key off or in Acc.
The VTD is the Vehicle Theft Deterrent and it disables the starting. It utilizes the thingie in the keyswitch with magnets and witchcraft (!) and such. Reading the description though, it says that it will disable either the fuel or the crank system depending on engine, but it never specifies which engine uses which system and only mentions disabling the fuel system. Then it mentions that the ignition switch activates the crank relay, regardless of Passlock status.
Here are the sections on the BCM and PCM for the VTD:
Body Control Module (BCM)
The body control module (BCM) contains the logic of the Theft Deterrent System. The BCM provides the battery positive voltage to operate the Passlock™ sensor. The BCM also measures the voltage of the security sensor signal circuit. The voltage measured will indicate whether the Passlock™ sensor has been activated and whether the resistance value from the sensor is a valid value or the tamper value. If voltage measured is in the valid range, the BCM compares this voltage, voltage code, to a previously learned voltage code. If the voltage codes match, the BCM sends a class 2 message containing a password to the powertrain control module (PCM). If the voltage codes do not match, or the voltage is in the tamper range, or there is a circuit fault, the BCM will not send the correct password to the PCM, and the vehicle will not start.
Powertrain Control Module
The powertrain control module (PCM) contains the remainder of the logic of the Theft Deterrent System. If a class 2 message containing a valid password is received from the body control module (BCM), the PCM will continue to allow the fuel injectors to operate. The PCM will allow the fuel injectors to operate until it decides there is no valid password coming from the BCM. If the PCM does not receive a class 2 message, or receives a class 2 message with an incorrect password, the engine will crank and will not run or will start and stall immediately.
At the end of the BCM section, it just says that the vehicle will not start, but it doesn't say that it will or won't crank. I kinda think the assumption is that it will crank and not start, but I'm not sure. If it only disables the fuel injectors, and still allows it to start, then that system is not where the problem lies. Or lays. Whatever.
The solenoid side of the crank relay is connected to the PCM on both ends so the PCM provides both power and ground. I can imagine that the ignition switch tells the PCM to crank and it provides power to the relay, then the BCM tells the PCM to crank and the PCM provides the ground.
I'm about ready to drive the three hours, swap rigs with her and carry testing equipment with me until it doesn't start.
Have I told you that I appreciate you sticking with me on this? I do. Very much.
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