TCM read erro loc 64800

[JuniorCruzer]

As far as I know it is a stock PCM. I bought the truck used, so cannot be 100% certain.

I have a trailer brake controller on the truck, I infomred the guys HP, did not concern them. Only other item I have is radar detector. Disconnected that to make sure it was not causing some cosmic interferance.

I have nothing else connected to the truck, stock stereo, stock batteries, stock motor and tranny.

Working on a few things with them, so we will see what comes of it.

Thanks!!!

Jon

[Dynomike299]

I pull the TCM fuse for 30 sec and the tune goes with no issues????

[JuniorCruzer]

I pull the TCM fuse for 30 sec and the tune goes with no issues????

What do you mean you pull it for 30 seconds? right when you start tuning? When it begins to error out? Can you explain a bit more?

Jon

[TwoFast4Lv]

dang never seen this before. Still having this issue also Only fuse that makes it better is when I pull the Trans fuse and it is not read at all

Maybe we could add a box to not read the trans? it really cuts down on read and tune time!

[GMjohn]

I am having this issue also. 04 k2 LB7.

I fail reading at the same location using .18 HPT software.

Actually I fail consistantly at 64C00, Every time on the trans controller.

For what I would like to change I guess I can just pull the tcm fuse but it bothers me that I can not read the TCM. I am thinking about making a jumper wire for the star connector to connect pin 2(ALDL) to the ECM and TCM to eliminate any possible interference. Need to pull diagrams to sort out but not sure what to try next. Any suggestions?? I was able to program with a tech 2 without issue.

John

[Bill@HPTuners]

Have you tried reading in low speed mode?

[GMjohn]

I have, oddly enough it fails in a different location. Actually reads a little bit more.

First attempt with a 2.8 ghz P-4 laptop. USB 1.1

Going to try my other laptop today.

1.7 ghz P-M USB 2.0 to see if a bigger data pipe has any effect.

John-

[CRASHNBURN]

I wonder if you need a usb 2.0. for it to work?

[Bill@HPTuners]

na 1.1 should be fine as long as your running the latest public version.

Any inline modules, onstar or anything that might be on the same databus as the pcm/tcm?

[turbo lcc]

Bill is there anyway you guys can give us a check box or something so we can choose if HPT reads the TCM or not?

[Bill@HPTuners]

Already in the main request thread http://www.hptuners.com/forum/showthread.php?t=6619

[CRASHNBURN]

Good add.

[GMjohn]

No difference with the USB 2.0

I saw some previous post's with overrun issues, hoped this would do it.

ECM dumps fine it's the TCM I have issue with.

If it helps anything here is my info log-

John

[GMjohn]

Tried again with the 2.8 usb 1.1 machine in High speed.

Failed- again in the TCM. This time I consistantly received the error-

Invalid byte count in block transfer.

I did however manage to download the second try turning off high speed transfer.

23 minutes for an ECM - TCM download.

Question- I have lost faith in my ability to reliably read write this combination.

Bottom line I am afraid to do a write, I am a little gun shy because I have scrambled multiple computers in the past ( I will also add Not using HPT) but been there before. If I can not do a reliable read, I am not going to do a write. I don't have any duramax bins to fix things with if I get into trouble.

Any suggestions for reliable comms?

Prey and use slow speed??

Thanks for any suggestions

John-

[Chris@HPTuners]

you should be ok on the write, it's just the read that gives problems. i'm going to look into it when i get a chance.

[blued turboed1]

Seems that reading in lowspeed mode would do the trick.