Found this out tonight that is works even on 05 and 06...Only one catch you'll have to borrow someones 00-05 chevy impala. Tryed it on an 04 and then my own 06 gt earlier this evening with remotes I got with a bunch of parts at the salvage yard.
Basically what you do is remove your keyless entry reciever, put it in the impala, then access the remote learn function in the impalas factory stereo. Once you learn the remotes using the impala you put the recever back into the grand prix and your all set to go your allowed up to four remotes programmed, and you must have all remotes with you that you wish to use after this procedure. This is for cases where a lost remote will not work after programming new remotes.
To accomplish this you dont need any tools and it only takes me about 4 minutes
The reciever on the impala is located near the bottom of the windshild near the left of the defroster vent...so you remove the fuse panel cover on the left side of the dash, then the windshield piller then lift up partially the winshield/defroster trim and you will see the small square remote keyless entry box you remove this by pushing in the side tabs on the right of the box and remove and unplug.
Then you go to the grand prix and remove your keyless entry reciever...on the 04 model its located under the windshield trim but to the right of the defroster vent so same steps as the impala.
on 05-06 grand prix's its located on the rear window deck, almost next to where the compass module is however you do not have to take the back seat and all that out to get it heres my trick...
When you look inside the trunk between the two speakers you will see either a large opening where the factory amp sits if equipped.
if you dont have an amp just reach your hand up up there and then forward and unlatch the keyless entry module and pull it back through the hole and disconnect the wires going to it.
(you will know where it is because you see the tabs that hold it there clipped into the metal).
If you have an amp you will have to disconnect all the connectors and leave them dangle, this give me just enough room to stick my hand in there and grab the reciever.
After i got the reciever out i went over to the impala and plugged it in then turned the key on. You then have to turn the radio off then hold the center button on the bottom dial until settings is displayed, then press seek until program fob(or similar) is displayed then press 1 or 2 then hit that center button again. it will then show push fob...you hold the unlock and lock buttons at the same time for about 10 sec's and you will here a short beep when programmed, for any more remotes just proceed to the next remote right after the beep, when all done just turn the ignition off and return the reciver modules to the rightful cars.(this procedure is also explained in the impala owners manual)
While this does seem like a lengthy procedure it really does not take me more then 4 minutes...if you have not removed these mouldings before just take your time.
It really beats paying the dealer roughly 80 bucks in some areas just for programming these things.
I would not think this would work with the 07-08 models since there keyless entry modules are directly linked to the class 2 data lines because of the tire inflation sensors that communicate using the keyless entry module. rather then a dedicated wire going to the bcm just for the reciever as in 04-06.
This diagram shows the keyless entry reciver location on an 05-06 grand prix...(notice how it clips into the metal deck and the big hole you can reach up from inside the trunk.
http://compnine.com/index.php?u=1&year= ... rouptype=BThis diagram shows the location on the 04 grand prix's, same ides how it clips in. its around where the number 7 is
http://compnine.com/index.php?u=1&year= ... rouptype=BThis diagram shows the keyless reciever location on the 03 impala.
Number 44 shows where it goes.
http://compnine.com/index.php?u=1&year= ... rouptype=B
