Prom in ECM Backwards
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
Prom in ECM Backwards
Hypothetical (mostly). What happens if you put the prom into the ecm (82 ecm) backwards and apply power. After the "pop" what is damaged - the prom or the ecm or both.
Admit, I did this several years ago and went to the stock prom, not the backwards hypertech. Did that have any negative effect on the ecm? Had to replace the ecm last week and car is running as good as ever now. Wonder if I screwed the pooch on the backwards insertion of the prom. I know all about how to do it right. But I still did it backwards.
Admit, I did this several years ago and went to the stock prom, not the backwards hypertech. Did that have any negative effect on the ecm? Had to replace the ecm last week and car is running as good as ever now. Wonder if I screwed the pooch on the backwards insertion of the prom. I know all about how to do it right. But I still did it backwards.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
OHhhhhhhh...That sux for sure! You should be OK with the ECM, but the PROM is toast for sure. It applys power where it shouldn't when in backwards. The best way to prevent that from happening in the future is to mark the PROM with a dab of white paint on pin #1 and on the socket or use a silver magic marker. Hope all goes well. 
Last edited by Buccaneer; Aug 15, 2018 at 10:42 PM.
Burning Brakes
Joined: Nov 2014
Posts: 946
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From: Foothills of the Adirondacks.
OHhhhhhhh...That sux for sure! You should be OK with the ECM, but the PROM is toast for sure. It applys power where it shouldn't when in backwards. The best way to prevent that from happening in the future is to mark the PROM with a dab of white paint on pin #1 and on the socket or use a silver magic marker. Hope all goes well.
Most PROM are toast if you plug them the other way around.
Safety Car
Joined: Nov 2005
Posts: 3,532
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Yeah...I know that, but for others that may overlook that it helps to have a reminder (white paint or whatever) to match up the color ends together...Jus sayin'.
Burning Brakes
Joined: Nov 2014
Posts: 946
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From: Foothills of the Adirondacks.
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Safety Car
Joined: Nov 2005
Posts: 3,532
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
OK, that's just not true. The 82/84 EPROM or EEPROM Corvette or 82/83 Camaro, Firebird and Trans AM are not any more susceptible to static or ESD damage than any other EPROM/EEPROM made. If the discharge from your body or whatever else is high enough, it can zap a chip without you knowing it until you plug it in. It is ALWAYS good practice to ground yourself properly before handling those type of devices. Glad you got it fixed.
Racer
Joined: Oct 2017
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From: Henry county ohio
Still doesn't change what I said, the chips are susceptible to ESD damage. I never messed with anything other than the Z-28 chips, and have pulled a few out of brand new packaging, using a ground strap on my wrist, not touching anything but the body of the chip and they were DOA. Doesn't really matter, after I sold my Z, went and bought a 2001 Cadillac ESC, no chips to play with, just reprogramming the whole ecm. Now I just set the cruise, play with the radio, and keep it between the lines. Cheers
Drifting
Joined: Aug 2004
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From: Lubbock TX
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Still doesn't change what I said, the chips are susceptible to ESD damage. I never messed with anything other than the Z-28 chips, and have pulled a few out of brand new packaging, using a ground strap on my wrist, not touching anything but the body of the chip and they were DOA. Doesn't really matter, after I sold my Z, went and bought a 2001 Cadillac ESC, no chips to play with, just reprogramming the whole ecm. Now I just set the cruise, play with the radio, and keep it between the lines. Cheers
The 82/84 EPROM or EEPROM Corvette or 82/83 Camaro, Firebird and Trans AM are not any more susceptible to static or ESD damage than any other EPROM/EEPROM made.
Racer
Joined: Oct 2017
Posts: 312
Likes: 64
From: Henry county ohio
Dudeman turn off your flamethrower and read the first sentence you wrote. All I did was comment that in my experience, the chips that I have encountered, have been delicate. Fortunately, I have progressed beyond chips.
To the OP, I apologize if I have given you incorrect information.
To the OP, I apologize if I have given you incorrect information.
Advanced
Joined: Apr 2018
Posts: 60
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From: Northern Kentucky
WOW! I guess people just don't read what is posted and only what they want to read. Here's what I said in reply...
This is a TRUE statement in itself. I'm not or wasn't saying that you did not have a blown chip or that you did not received bad chips DOA that you mentioned in your last post, it happens and that's why we stopped burning PROM chips for the 84. One, they were and still are hard to find and even in quantity and two, they have a somewhat high failure rate. This DOES NOT mean that they are more easily damaged by static than others, it just happens just like any other chip made that is ESD sensitive. After working for Motorola in the semi-conductor sector for a number of years, I can tell you a lot about ESD and chips and how easily they can be ruined... jus sayin. I hope this clears up my first reply, if not, what can I say?
This is a TRUE statement in itself. I'm not or wasn't saying that you did not have a blown chip or that you did not received bad chips DOA that you mentioned in your last post, it happens and that's why we stopped burning PROM chips for the 84. One, they were and still are hard to find and even in quantity and two, they have a somewhat high failure rate. This DOES NOT mean that they are more easily damaged by static than others, it just happens just like any other chip made that is ESD sensitive. After working for Motorola in the semi-conductor sector for a number of years, I can tell you a lot about ESD and chips and how easily they can be ruined... jus sayin. I hope this clears up my first reply, if not, what can I say?
Last edited by Tslayer66; Aug 24, 2018 at 12:18 PM.
Race Director
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From: South Western Ontario
Last edited by lionelhutz; Aug 24, 2018 at 03:19 PM.