So I'm at my wits end... Today I can't even get back to the point I was at yesterday... I haven't been able to get into recovery once or get any output other than failed to unlock... Super confused and I'm really starting to think my obdlink SX is defective or something... I just don't know what it could be at this point... It almost has to be something in my setup.
Here's a summary of things done so far:
I'm on a battery now with 12.9v
PCM Connector that came with my harness is a real GM unit rather than the repo that came with it
I've checked resistance of all the wires, pcm to obd port, pcm to battery + / -, obd port to battery + / - and they all read about .6 Ohm
All I can think now is that my initial messed up flash was so horrific that it somehow irreparably damaged the computers...
I'm nervous about getting a 3rd computer to try again because we still don't know why this isn't working but that's starting to seem like the only option aside from sending one of these bricked ones out to someone to have them see if they can recover it... What a mess! haha...
You should have done some CAL data writes only first, to confirm all is good with the setup, and is much easier to recover if something goes wrong.
Once you get confidence with the setup, do a full clone or OS write, it is always a good idea to hook a fully charged battery, on a critical clone write to avoid disaster.
kur4o wrote: ↑Sat Apr 05, 2025 3:10 pm
You should have done some CAL data writes only first, to confirm all is good with the setup, and is much easier to recover if something goes wrong.
Once you get confidence with the setup, do a full clone or OS write, it is always a good idea to hook a fully charged battery, on a critical clone write to avoid disaster.
Thanks, definitely a learning experience. Thankfully these computers are pretty common so at least getting another and having someone else do this shouldn't be too painful...
I'm pretty sure that with this second computer I did do a calibration write when things bricked but it's been so long now that I'm struggling to remember. All I was doing that time was trying to successfully remove VATS. I know the first computer I did a clone because I needed to change the OS so I could segment swap the transmission since I couldn't find a 4l80e bin for that os or xdf files.
If you want some help mate, you could send one of the PCMs to me, I can see if I can recover it. At least then you will know if you've actually ruined them or not. I'd guess they will be recoverable. Pm me if you want
Corrupted flash or bad OS would be unlikely to cause a fault like that. You'd be more likely to get nothing at all, working recovery mode or running OS on the bench but other DTCs or functions not working in car. 12.9v battery power rules out the power supply so now its sounding like interface hardware problem or software problem on the pc. If you are prepared to spend some money to try and get working probably best to buy an obd xpro interface. The scantools are the slowst and most problematic type of interface.
antus wrote: ↑Sun Apr 06, 2025 1:53 pm
Corrupted flash or bad OS would be unlikely to cause a fault like that. You'd be more likely to get nothing at all, working recovery mode or running OS on the bench but other DTCs or functions not working in car. 12.9v battery power rules out the power supply so now its sounding like interface hardware problem or software problem on the pc. If you are prepared to spend some money to try and get working probably best to buy an obd xpro interface. The scantools are the slowst and most problematic type of interface.
Honestly, for only 30 bucks more than the SX I have now I'm thinking that might be worth it... I've lost any faith that my current one is capable given how unpredictable it's been. Going to do a return on that since I'm within the 30 days. If that one I linked to, the OBDX pro VX is the one you're referring to I'll place an order, it looks like they're in stock for the US currently.
I'm pretty confident the PC isn't the issue, it's a fresh win 10 install, fully updated, and I followed the steps for getting the driver for my scantool installed. I had also been trying with a completely different computer with the same lack of results.
antus wrote: ↑Sun Apr 06, 2025 1:53 pm
Corrupted flash or bad OS would be unlikely to cause a fault like that. You'd be more likely to get nothing at all, working recovery mode or running OS on the bench but other DTCs or functions not working in car. 12.9v battery power rules out the power supply so now its sounding like interface hardware problem or software problem on the pc. If you are prepared to spend some money to try and get working probably best to buy an obd xpro interface. The scantools are the slowst and most problematic type of interface.
Honestly, for only 30 bucks more than the SX I have now I'm thinking that might be worth it... I've lost any faith that my current one is capable given how unpredictable it's been. Going to do a return on that since I'm within the 30 days. If that one I linked to, the OBDX pro VX is the one you're referring to I'll place an order, it looks like they're in stock for the US currently.
I'm pretty confident the PC isn't the issue, it's a fresh win 10 install, fully updated, and I followed the steps for getting the driver for my scantool installed. I had also been trying with a completely different computer with the same lack of results.
I use the older version of that and it has been rock solid.
Phoenix wrote: ↑Mon Apr 07, 2025 4:25 am
I use the older version of that and it has been rock solid.
So I've seen this called out a few places too and I'm wondering if QA or some other change with the SX cable has made them less reliable than the older ones... There is still the very real chance that something unexpected in my setup is messing stuff up but I'm struggling to figure out what it would be.
I have nothing good to say about the scantool cables. The protocol is slow and bad, the hardware is slow and I regret ever trying to support them in the first place. We also seem to have more reports of failed interface hardware but that could be because more people buy them because they are easier to find for newbies starting to play with this stuff so there may be more of them out there. lsdroid has dropped support for them, I would love to but that will be a dis-appointment to those who are using them now for occasional tweaks to their calibration and aware of the slow speed. I am still very tempted to drop them for the next release of pcmhammer though. Its hard to know how many new problems will come up with the newly supported computers.
antus wrote: ↑Mon Apr 07, 2025 4:56 pm
I have nothing good to say about the scantool cables. The protocol is slow and bad, the hardware is slow and I regret ever trying to support them in the first place. We also seem to have more reports of failed interface hardware but that could be because more people buy them because they are easier to find for newbies starting to play with this stuff so there may be more of them out there. lsdroid has dropped support for them, I would love to but that will be a dis-appointment to those who are using them now for occasional tweaks to their calibration and aware of the slow speed. I am still very tempted to drop them for the next release of pcmhammer though. Its hard to know how many new problems will come up with the newly supported computers.
That obdxpro is the right one.
Fascinating. I got mine not necessarily because it was cheap, but because I thought I was playing it safe going with something straight USB vs the others listed as supported that used BT. I didn't understand the difference between all of those scantool options vs something like the obdx.
Going to get one ordered today and see where that gets me. Regardless of if I can fix these computers having something that will work for the future as changes or troubleshooting is needed is important to me.
