JTEC+ connection problems

[hskrRT]

Im just trying to read my 99 Dakota R/T PCM so I can look at tune. not even trying to change anything or upload file. it will gather the PCM informetion and disoplay it, but when I try to read entire it tells me to turn ignition off, then says VPP failed. if I don't turn ignition off, then it says baud rate failed.

the truck was originally a Canadian truck. according to part number sticker on the PCM, its a 5.2L PCM, but does have correct VIN displayed, and the part number for PCM that is read by HPTuners is correct for a 99 R/T with federal emissions. Im assuming the PCM was replaced at some point. Id like to be able to tune this truck as it has several Mopar performance parts on it. not sure if there is a custom tune already on it or not.

[hskrRT]

Think I have some other electrical gremlins to sort out. Thanks for any thoughts about replying

[uarperformance]

You are using an MPVI2 correct?

[hskrRT]

MPVI3

got it figured out. Previous owner, or one of them, removed the 50 amp park lamp/interior light fuse in PDC under hood. probably due to before mentioned electrical issues. Without the fuse, you lose the constant 12vdc signal to OBD2 port. but with it in, there is constant power to ABS relay and power windows. I can roll windows up/down even with ignition off and key out.

So I was able to read and save the base file from PCM. but now I have a conundrum. I have a Mopar PCM from a 99 5.2L 4x4 in the truck now because I was troubleshooting shifting issue and needed higher rev limiter. so do I keep and modify that, or put the PCM with stock R/T tune back in? Looking through the different pages in HPtuners, I didnt see a speed limiter setting. and I know there are a few other things the Mopar PCM changes that can't be changed, even with SCT.