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TCM Compatibility 4L80E/Scooby Doo mystery

Kelleys_Hero

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So, I bought a "2001" HMMWV, which has a 4l80E in it which has an EPROM. The vehicle was in limp mode, and the TRANS light was on, but would not launch diagnostic codes. removed TCM which is contained in a 'waterproof' box, to find it is nearly filled with water. I removed the TCM and lightly brushed the board with a toothbrush and distilled water and replaced it back in the unit (after it dried). I had also found a bad/nearly severed wire which was the diagnostic wire (the E). Now the trans light does not light up...at all. My plans are to test out more of the wiring, ground and power supply before I write the TCM off as "fried". This is where the mystery starts for me...

The TCM is part # 16196390, or TCM390M at Oreillys', which is only $90 if they still were making them, and I could just plug in the EPROM (if it still works). The market from parts scalpers are wanting $400-$1000 for old/new stock, and I'd really rather not pay that if there are other ways. Some of the HMMWV forums people have told me that any 4l80e TCM will work, but I am not sure. Was looking at the TCM609M ( part # 16147609 ) and it looks identical (EPROM & wire connectors) to the one I need. Any thoughts from people that are more experienced with this sortof stuff?
 
They come up on Ebay . I have a couple of the early and later models . Easy to spot . The female connectors have no color around them like purple , red , blue , tan , etc . Plain finish with 2 cavities . Think I paid around $100 . Any time a 93 or earlier truck or van comes up for sale or parts , with the 4L80E , I look . So you are looking for the DB2 throttle cable in a van or truck . Watch out for the vans as they are odd at times . Came across a 95 G van that have a DB2 and no turbo . Looking into this it appears that model has 4 different 6.5s and one of them is a non turbo with a PMD .
 
Have been searching other part numbers and ran across a different part # (73-80106) made by Cardone. Its only $230 which is more than the original $90 dude, and it looks like it matches the same model year vehicles 94 thru 99. If I was gonna make some cool awesome truck, I might consider some expensive aftermarket controller, but for now its gonna be a farm truck...nothing fancy.
 
Hopefully your eprom is still good. if not there are ways to get one. there should be a code on the eprom chip. some searching online you might be able to find one for sale, but they can also be made. I have an eprom programmer and a few saved prom files for various vehicles. I think I have a couple of one for a TCM. all you'll need is a blank prom chip to write the data to.

on the TCM you have, when you dried it out, did you open up the case and clean it? I'm sure the water it was sitting in was nice and nasty! usually a good washing with some 91% rubbing alcohol and a light scrubbing with an old tooth brush will clean all the nasties off, brush it softly not to damage any of the components. look for any corrosion on any of the components. remove the eprom from it and clean there too. then after it's as clean as you can get it, put a layer of rice in a bin, set the board on the rice and then pour rice over it. let it sit un-covered in the heat out doors or in a dry area for at least a week. you can use compressed air to blow off any wetness from the alcohol off but don't use full air pressure. maybe 30 psi at most on the blow gun.

while the TCM is drying, clean up the connectors and whatnot, and then start checking power and grounds with your multi-meter, and other pins in the connector for contintenuity to the trans connector. this way you know all the wiring is good when you attempt to re-install the TCM, plus if you have to replace it, you'll know your not gonna fry the replacement too!
 
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Hopefully your eprom is still good. if not there are ways to get one. there should be a code on the eprom chip. some searching online you might be able to find one for sale, but they can also be made. I have an eprom programmer and a few saved prom files for various vehicles. I think I have a couple of one for a TCM. all you'll need is a blank prom chip to write the data to.

on the TCM you have, when you dried it out, did you open up the case and clean it? I'm sure the water it was sitting in was nice and nasty! usually a good washing with some 91% rubbing alcohol and a light scrubbing with an old tooth brush will clean all the nasties off, brush it softly not to damage any of the components. look for any corrosion on any of the components. remove the eprom from it and clean there too. then after it's as clean as you can get it, put a layer of rice in a bin, set the board on the rice and then pour rice over it. let it sit un-covered in the heat out doors or in a dry area for at least a week. you can use compressed air to blow off any wetness from the alcohol off but don't use full air pressure. maybe 30 psi at most on the blow gun.

while the TCM is drying, clean up the connectors and whatnot, and then start checking power and grounds with your multi-meter, and other pins in the connector for contintenuity to the trans connector. this way you know all the wiring is good when you attempt to re-install the TCM, plus if you have to replace it, you'll know your not gonna fry the replacement too!
I'm hoping the EPROM is good. It is CZSU one which was only used in 2001 with the HMMWV. Interestingly enough the technical manual states it has downward compatibility to 1997 and are interchangeable to 2007. Not sure what the difference between the words "interchangeable" and "compatibility" maybe in this case...

I did lightly brush the board a few days back with a toothbrush, but I used distilled water. I just tested power from batteries and ignition switch and getting 12v. Grounds have continuity from harness to frame. Gonna test transmission lamp next just to make sure it's still working, I'm still scratching my head as to why it stays off. I'm thinking when it was full of water maybe it was shorting out, as the light was dim.
Thanks for your response!
 
Looks like the OE part number for it is 5716028 for a non turbo application. keeping our fingers crossed the TCU is still good as with the eprom. there is one site online selling one for $132.

I looked at what eprom files I have, looks like the only one for a TCM I have is BACX which used TCM part number 16147609 from 92-93 diesel trucks with the 4L80E trans
 
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