1999 grand am bcm programming?
molten vett
08-24-2008, 01:26 AM
Hi guys ,hope you can help me.I have a 1999 grand am se 4cyl.heres the problem my sunroof had a bad leak and it rained in the car for about a week while i wasn't driving it. the floor was soaked and when i tried to start it ,it starts and cuts right off.the security light stays on but doesnt flash also the door locks dont work.A mechanic buddy of mine suggested the ignition switch(the electrical part with the wire connections not the part that the key goes in)he had one he uses for testing so i tried it and still the same results. i even tried the 10minute key reset.So i looked under the glove box and notice the bcm is wet so i take it out and it has water in it:banghead: i tried to dry it out but no luck. so i go to the junkyard to get another one. they have no grand am's so someone working there suggests using one from a 98 alero. it's 10bucks so i figure what the heck. I go home plug it in and the chime and door locks start working but no start:crying: It wont even start and stop with this bcm. With the old one every once in a while it will start but if i cut it off it wont re-start. My question is does the new bcm have to be flashed or programmed or do i have to get one from a 1999 grand am? someone please help me i dont know what to do next:runaround: One more thing i notice the old and new bcm have different numbers on top. sorry for the long post but i wanted to share all the info.
xeroinfinity
08-24-2008, 12:09 PM
Welcome to AF!
I would suggest fixing your sunroof drain leaks BEFORE you replace the BCM or it'll toast the repalcement.
MY GA GT done this twice, 1 new BCM and a used bcm. Mine never was soaked , but water would run over the fuse boxes that was what caused mine to blow.
Yes they do need it programed with the Tech II scan tool at your local stealership, $40-60 should cover it.
And I dont think it was a 98 Alero, it had to be a 99 or up, I dont know if it would work as their different components in the sister car.
Once you dry out your old BCM it should still work for starting , but you'll have a SVS light on and might loose other little things like interier lighting.
So you could have other issues causing your no start.
Good Luck
I would suggest fixing your sunroof drain leaks BEFORE you replace the BCM or it'll toast the repalcement.
MY GA GT done this twice, 1 new BCM and a used bcm. Mine never was soaked , but water would run over the fuse boxes that was what caused mine to blow.
Yes they do need it programed with the Tech II scan tool at your local stealership, $40-60 should cover it.
And I dont think it was a 98 Alero, it had to be a 99 or up, I dont know if it would work as their different components in the sister car.
Once you dry out your old BCM it should still work for starting , but you'll have a SVS light on and might loose other little things like interier lighting.
So you could have other issues causing your no start.
Good Luck
molten vett
08-24-2008, 01:23 PM
Welcome to AF!
I would suggest fixing your sunroof drain leaks BEFORE you replace the BCM or it'll toast the repalcement.
MY GA GT done this twice, 1 new BCM and a used bcm. Mine never was soaked , but water would run over the fuse boxes that was what caused mine to blow.
Yes they do need it programed with the Tech II scan tool at your local stealership, $40-60 should cover it.
And I dont think it was a 98 Alero, it had to be a 99 or up, I dont know if it would work as their different components in the sister car.
Once you dry out your old BCM it should still work for starting , but you'll have a SVS light on and might loose other little things like interier lighting.
So you could have other issues causing your no start.
Good Luck
Thanks for the info. i've already sealed the sunroof so this shouldnt happen again. also did the used bcm you used come from the same year grand am that u have? and if so did the numbers on top match.
I would suggest fixing your sunroof drain leaks BEFORE you replace the BCM or it'll toast the repalcement.
MY GA GT done this twice, 1 new BCM and a used bcm. Mine never was soaked , but water would run over the fuse boxes that was what caused mine to blow.
Yes they do need it programed with the Tech II scan tool at your local stealership, $40-60 should cover it.
And I dont think it was a 98 Alero, it had to be a 99 or up, I dont know if it would work as their different components in the sister car.
Once you dry out your old BCM it should still work for starting , but you'll have a SVS light on and might loose other little things like interier lighting.
So you could have other issues causing your no start.
Good Luck
Thanks for the info. i've already sealed the sunroof so this shouldnt happen again. also did the used bcm you used come from the same year grand am that u have? and if so did the numbers on top match.
xeroinfinity
08-24-2008, 01:44 PM
Yes the ones I have used were the same year and the same options, power windows, power seat, etc etc. ANd the part # was the same but the serial I think was different for everyone.
I was going to mention the sun roof gasket was also part of this issue.
I sealed mine the first time , the silicone didnt work well on the rubber gasket and it leakd before I got to the drains.
They leak right where the hose is put on sun roof drain tube, mine were caused when the paint shrank and split the tubing. :banghead:
I just cut and spliced a new section insted of replacing the entire thing .
I was going to mention the sun roof gasket was also part of this issue.
I sealed mine the first time , the silicone didnt work well on the rubber gasket and it leakd before I got to the drains.
They leak right where the hose is put on sun roof drain tube, mine were caused when the paint shrank and split the tubing. :banghead:
I just cut and spliced a new section insted of replacing the entire thing .
smblockchevy
09-18-2008, 10:27 PM
you cant use a bcm from another vehicle you have to get a new one from a dealership. there is no programming to a bcm in a grand am. the dealership will simply set up your new bcm to you vehicles options and do the 10 minute relearn. once all of this is done the bcm becomes locked and cannot be used in a different vehicle.
xeroinfinity
09-18-2008, 10:32 PM
Well thats funny, I have a "used" BCM in my GAGT and it works fine, after the relearn. But only the same make model and year will work.
molten vett
09-19-2008, 01:15 AM
Well thats funny, I have a "used" BCM in my GAGT and it works fine, after the relearn. But only the same make model and year will work.
I got a bcm from the junkyard ,same year same model number but the dealer is telling me they cant be reprogrammed:crying:
I got a bcm from the junkyard ,same year same model number but the dealer is telling me they cant be reprogrammed:crying:
xeroinfinity
09-19-2008, 07:39 AM
I got a bcm from the junkyard ,same year same model number but the dealer is telling me they cant be reprogrammed:crying:
Sounds like they are wanting to sell you a new one for $400 or so.... :disappoin
Have you tried plugging it in ?
I would disaconnect the battery before attempting to hook up the used BCM. ;)
Sounds like they are wanting to sell you a new one for $400 or so.... :disappoin
Have you tried plugging it in ?
I would disaconnect the battery before attempting to hook up the used BCM. ;)
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