looking back through the threads, I might have to look and see if I have a power problem-The original "won't talk" problem was caused by not getting enough power to the PCM, so maybe I've just got a shit battery/loose wire somewhere?
looking back through the threads, I might have to look and see if I have a power problem-The original "won't talk" problem was caused by not getting enough power to the PCM, so maybe I've just got a shit battery/loose wire somewhere?
There is definitely some noise interference when the engine is runnig. Maybe the PCM grounds are not good, or some other wiring. The PCM should get only grounds through the wires and should be isolated from chasis. Interesting only data for 01 message is corrupt the broadcast messages that follow immediately are good. May be related to patch in some way.
Causes could be, patch, baud rate problems at ftdi chip due to noise.
Or some wiring problems.
I should look first at aldl cable first, than wiring and grounds.
What model aldl cable are you using. I ve seen some ftdi chips that just dont work, or work sometimes.
It's a homemade one, based off the tutorial here. It's worked fine in other cars, and works fine to flash the PCM, and it works fine as long as the engine isn't running. I think I might have a grounding issue or something somewhere, I'll check it out today.
the 24X sensor value should stop updating after the PCM starts to ignore it(~1250RPM for a FWD calibration and I think 2000ish for RWD). why GM chose to split those RPM thresholds, I don't know.
I've had some FTDI boards act funny before, but it usually takes some abuse before that happens. my ALDLCable.com version lasted about a year before it started getting wonky, then I built my own. unfortunately, due to the 8192 baud speed, options are somewhat limited. the CP2102 can be made to work, but I can't really say if it's any better. at this point, my USB ports themselves are getting kind of worn out and contributing to me shallow breathing during a flash.
with a 2.1MHz clock speed, even a 250nS PROM is going to be more than fast enough for a nearly 500nS cycle. stock PROMs should be 120nS though.
the hell is it with the patch function lately? I've never seen it do that before, let alone twice with one BIN. i'll have to see if Mark can replicate it and verify it as an actual bug rather than us screwing something up.
the data given out after a crank attempt looks like typical mode 0 data(trip computer and some digital dash stuff). then for engine running, the "response" literally filling up the data queue with repeating values is certainly something else causing interference, but being that repeatable is odd, I would expect some dithering of the signal.
1995 Chevrolet Monte Carlo LS 3100 + 4T60E
It has got to be something to do the truck wiring. I cant find any serious noise, the ICM tests fine, the alternator tests fine, the best battery tests fine, but no dice.
Going to go through all the grounds and all the supply lines again, and see if I have a loose ground or something. I started down that road and had to stop due to the rain.
Ok, so the truck runs continuously now-but it's so super rich it chokes out. No big deal, just flash an update tune...Nope. Bricked another PCM.
Turns out it's my laptop's USB ports that are the issue. They're flaking out left and right.
So, I've got a TL866 programmer, and MicroPro. I've got a BIN file that I'd like to flash to the two chips. How do I go about splitting the file and programming it? Apparently this is going to be a regular thing for a bit...
I've got another laptop that I'll set up to run tonight. It's so close to being drivable! If I can get it leaned out enough to idle and datalog, it'll be a quick job to tune it up, just gotta get this flash programming under control.
So, programming the chips, no problem. How to split the bin, AND, which chip goes where...there's the issue.
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