Ecm prom code?
Thread Starter
Instructor
Joined: Apr 2012
Posts: 115
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Ecm prom code?
Hey guys I'm having some custom work done on my prom chip and the guy doing it needs a 4 letter prom code and I can't seem to find it anywhere, so far I've only found 3266 and referenced that online to find "hlp" no four letter combos, I hope to send it out tomorrow morning but I can't find this code anywhere!
By the way I have an 85 corvette 4 speed car if that helps any. Thanks ya'll
By the way I have an 85 corvette 4 speed car if that helps any. Thanks ya'll
Team Owner
Joined: Sep 2003
Posts: 20,170
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
I bummed. All the links saved when I was investigating my prom number are gone.
efitune.org was the best for crossreffeing
efitune.org was the best for crossreffeing
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
The BCC (BroadCast Code) is on a silver label on the EPROM in the ECM:
There are different broadcast codes for the year, auto vs. manual trans and rear end ratio.
Yours will probably be a 3 letter code. They went to 4 letter BCCs around '88 or so.
There are different broadcast codes for the year, auto vs. manual trans and rear end ratio.
Yours will probably be a 3 letter code. They went to 4 letter BCCs around '88 or so.
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
Last edited by MrWillys; Oct 22, 2013 at 11:37 AM.
Team Owner
Joined: Sep 2003
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There was actually 2 HLP ID's in '85 I believe. 3266 is one choice and 2297 the other. One was a calibration for both FED & CA the other a FED only and if you scanned them for an ID you would get different results.
The 3266 is I believe the most recent for one of several through the production and service changes.
If you wanted to actually ID your present PROM you could have it scanned at the ALDL and check your results. If it's a modified PROM I don't know. You can use this and enter a VIN to maybe confirm your ID or see the possible options. When this works it's very good information. There will generally be TSB's available and accessible if there's been changes. How current is it? I don't know any longer. The TIS application is quite old. I don't know that the CVN works any longer. I used a random '85 MT VIN and the results were all what I would have expected.
https://tis2web.service.gm.com/tis2web/
The 3266 is I believe the most recent for one of several through the production and service changes.
If you wanted to actually ID your present PROM you could have it scanned at the ALDL and check your results. If it's a modified PROM I don't know. You can use this and enter a VIN to maybe confirm your ID or see the possible options. When this works it's very good information. There will generally be TSB's available and accessible if there's been changes. How current is it? I don't know any longer. The TIS application is quite old. I don't know that the CVN works any longer. I used a random '85 MT VIN and the results were all what I would have expected.
https://tis2web.service.gm.com/tis2web/
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