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Resetting a replacement 2005 Deville PCM

2321 Views 4 Replies 5 Participants Last post by  sefiro
Dealer says I need a new PCM because the 2610 code won't stay off so I can't smog my car by California rules. I bought a used PCM programmed to my VIN with instructions on how to make it work. First it has to recognize my key or the car won't start. Instructions say to turn on ignition for about 10 minutes until the SES light goes off, then turn ignition off for 10 seconds or so then do the same thing 3 times and then it will start. Problem is the SES light never goes out after 10 mins or even an hour so I cannot go through the procedure. The car runs fine with the old module but at the end of this month, August, it will need to be smogged. All smogs fail in Califonia with the SES on even if the emissions test is OK.
I need to have the new PCM recognize my key so the car will start. Standard instructions for GM PCM as outlined above don't work for me.. What else can I do?
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PassKey III
This system uses a special key (PK3 stamped on the shoulder of the key) with a transponder under the rubber cover. The receiver module is located next to the lock cylinder. When the key is positioned next to the lock cylinder receiver module, it energizes the transponder which sends a coded signal to the receiver. The receiver module checks its memory to see if the signal is correct. If it is, the module sends a signal to the PCM to enable the engine. If the value is valid, the indicator light will remain steady for 2 seconds. You cannot test this system with an ohmmeter. You need a scan tool. If the signal is not correct, the PCM disables the injector and the starter and flashes the light once per second. If an illegitimate key is used or a system problem exists, the light flashes twice per second.

Maybe check this?^^^^^^^^

All I can think of is the new PCM/VIN is incorrect, a conflict between the PK3 receiver/BCM and the PCM.

An exciter located at the opening of the lock cylinder activates as the key is inserted. The exciter sends a radio signal that’s received by the transponder. The signal actually energizes the chip in the key head and the key responds by broadcasting a unique identity code that’s received by the Theft Deterrent Exciter Module (TDEM). The TDEM transmits the data to the BCM. The BCM consults its memory and if the identify code matches, it sends a fuel enable code to the PCM. If wrong, the BCM sends a fuel disable code to the PCM. The BCM is also equipped to detect an
theft deterrent exciter module

intermittent condition with the transponder. If it loses the code for one second, it sends a fuel disable code to the PCM and the vehicle won’t start. That’s why it’s always best to try a different key if you encounter a car won’t start security

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