I have 2 burned up pcms from laptop dieng while loading new tunes. My question is which chips on the boards are the usual suspects? I dont see any that resemble the old style socket eproms. anyways they are 94 lt1 computers and have them apart ..just need to know which ones or info on them so i can order some.

 

DIY Intel AN28F512 http://www.mindspring.com/~amattei/flashfix.htm

 

Both chips should say FLASH and AN28F512 on them. They are fairly easy to remove with a heat gun but if you don't have good soldering skills, I wouldn't risk trying to solder the chips or sockets in place. If you aren't careful you can blow the entire PCM permanently.

 

ok thanks for the info and i am in the electronics field and have some veterans that can help me solder if im not comfortable doing. now as far as the chips go. isnt there something besides the tune that has to be initially loaded onto the chips before the tune can be uploaded?

 

Yes, you need to burn in the original .bin files on them with an eprom burner before you put them back in and upload your tune. Socket the boards instead of re-soldering the chips back on. It will save you time in the future. You'll need an eprom burner to repair them yourself. If you go that route and decide to fix them yourself, you can reburn the chips, reload your tune, then pull the chips back out and read the new .bin files and save them on your computer. Then, if you ever lose them again, you can just load the already modified .bin. But most of us go through so many tune changes, it usually ends up being a case where you just load the stock .bin file on each chip 1st and then put it all back together to upload your own tune.

Ken R.

 

You can't use the pcm and tunercats to load the initial bin file to a blank chip?

here are sum pre-programed chips http://www.madtuner.com/index.php?pa...mart&Itemid=26

 

No, the reason why you cant just fire up Tunercat and reload iwith your 128kb fils is the "program" that tunercat/lt1-edit uses to communicate is disabled by just one of these chips being F-ed up... and each chip is only 64kb.... and if you remember where the PCM loading program process crashed (before 50ish % or after 50ish %) you can usually just reprogram the one chip that was corrupted... mine was the side with the Blue Connector...? Whatever one starts first - under 50% (2 chips, one is 50%, other is 50%, both = 100%).

The other tricky part is you cant just split your 128kb file in half, and flash each chip with the split files, you need a fresh uncorrupted 64kb image of each chip, E or T side.
I bought a willem programmer off ebay and re-flashed the chip using a "correct" E or T side flash after realizing all the above afterd days of greif, so know this: Full 128K "tunercat" bin files or "LT1" flashes will not write to the chip even if you somehow split them into 64kb files... they have to be original or actual E or T side images, all checks and verifications have to pass (from within the willem programmer software if you expect the chip to work.

 

I see, thanks for the info.

 

oh ok , very interesting how these work. so dookie454 did you actually pull the chips off the board or did you use the test points on the board and just reprogam the still on the board? Tunercat said that was an option when i asked them.also do you mind telling me which wellim you got off ebay? i just looked and seen several.and where did you get your "E" & "T" flashes from? sorry for the 20 questions, this is all new to me and really want to get this figured out.

 

yea I pulled the one chip off the board, got the files from this super duper guy:

http://www.akmcables.com/Obd1-t.bin
http://www.akmcables.com/Obd1-e.bin

"These are raw binary images that you'd use to flash in to a chip using an EPROM programmer or something like that. Note that address lines are swapped in the PCM, so you can't just split a .lt1 file in half and use half an image.
Let me know if you need anything else!
Cheers, Andrew"



As far as the programmer goes, it's an "Enhanched Willem EPROM programmer".. looks just like this, cant guarentee it's the same as mine though..
http://cgi.ebay.com/Enhanced-Univers...mZ130304592045

Until I got the correct files, I kept getting errors, I forget what they were now though.

 

awesome man !!that is a huge help thanks once again!

 

Sorry to bring up n old thread, but I am looking into this right now.
My PCM is OBDII though. Dont know if the chips are the same as the OBDI PCM uses.