Ugh, just fried another PCM by trying to program it for the 28lb injectors I just threw in and somehow LOST communication...

Car info: '76 Vette w/ '95 LT-1/4L60e, F-body PCM (16188051), Painless wiring harness, AKM adaptor cable.

I have no idea of why it lost communication (ALDL test was positive)
I tried programming using TunerCat V 2.23, while in Win98 (no screen savers or other programs running)

It was just starting to program (maybe 15%), then "lost communication" appeared and my PCM was ticking quite loudly and did not stop until the key was off. When I turned the key back on, both (I believe) fans came and stayed on!

I had a spare PCM from an F-body (Trans Am?) and hooked that up, but the car just ran for a moment, then stalled. I tried READING the PCM (using DOS this time), but communication was lost again and the following error message appeared: Fatal Error - Program Terminated, Program Error Code: 5, Program Error Address: 6538.

After the "Fatal error" message, I tried to start the vehicle, but it only cranked (never started and fuel pump wasn't priming). I then turned the car off and disconnected the battery for 30 seconds or so. Now the fuel pump primes again, but the car only runs for a few seconds then stalls.

1) Any suggestions on why this may be happening?

2) I didn't think you could get into "trouble" just by READING the PCM...???

All info appreciated!

 

Add'l info...

Had the car on trickle charger all night (just to be sure vehicle's power isn't an issue) and ran the ALDL Test program again with the following results:

Phase 1 (DTR only power), Phase 2 (RTS only power), and Phase 3 (DTR + RTS power only) ALL had "Timeout error receiving data, Phase "X" failed" errors.

Phase 4 (Enabling RTS + DTS power) and (Setting BAUD rate to 8192) had the result: "Failed to receive data. Verify that the PC serial port is correctly set-up."

I have no idea of what this stuff means, but since EVEYTHING failed, I'm thinking there's a problem here!?!?!

Ideas???

 

I once lost communication while flashing a 1995 Trans Am. I ended up sending the cable and PCM to Andrew at AKM. It turns out a connection in the cable went bad. Andrew sent me a new cable free of charge, and a very small fee to replace the flash chip(s) in my PCM. AKM/Andrew = Great Customer Service!!

 

Cool... I forwarded a copy of my post to Andrew @ AKM. Over the years, I have heard only good things about him. Hopefully he can give me some things to try or test, or if he needs the cable and/or PCM sent to him, that's fine as well.

 

Just rec'd a response from Andrew. WOW, you are correct... what customer service! He first recommended that I try a different ALDL testing program, PCMcomm.exe, from Carputing.com. It indicated all things are fine w/ my communication. I also downloaded their PCMread.exe program and successfully read my spare PCM. So, a little sigh of relief on that (I thought I may have fried BOTH PCMs!)

I did though, notice quite a bit of corrosion on my ALDL cable's pin #9 (S. FL humidity???). Andrew said he'd check out my cable and could also re-solder the "sockets" in my PCM. Pin #9 probably isn't always making good contact, so the test ran ok this time, but I'm hesitant to program until that connection is clean. Frying one PCM is enough for my budget!

I'll post as I know more...

 

I knew Andrew would help you out!!

Best of luck.
-Mike

 

You may have a bad download of Tunercat and it couldn't complete the read/program. You may want to re-download it to make sure its good.
Just a thought.

 

Eddie,

...bad download of Tunercat? Are you speaking from experience? I just pulled my ECM last night and brought it to work to check it out because I got CCM (central control module) codes C41, H41 (loss of ECM serial data communication) and "ERR" for the module 4 ECM code.

I had just downloaded the most recent version of tunercat and re-programmed the EPROM with the romulator. Fans now come on as soon as I turn the ignition on. I burned a chip at work and installed it directly, the result was the same.

Beth

 

Yes indeed! He repaired the cable, resocketed the chips in the PCM, sent me two spare chips, reflashed the program I was trying to flash, and sent everything back Priority Mail w/ tracking for even LESS than he originally quoted me!

Installed the PCM and reflashed my spare using the repaired cable and EVERYTHING worked GREAT!

Let's hope he NEVER finds another career!

 

for Andrew here as well, great service.