I really don't have a issue either.. just pulling the two radio fuses. But low speed.
I really don't have a issue either.. just pulling the two radio fuses. But low speed.
Tuner at PCMofnc.com
Email tuning!!!, Mail order, Dyno tuning, Performance Parts, Electric Fan Kits, 4l80e swap harnesses, 6l80 -> 4l80e conversion harnesses, Installs
If you have to use low speed you have an issue.
I also found that most vehicle security shops like to tap into the OBD port 12V power. P59s hate this. As soon as I notice communication issues, I look behind the port, and find that there is 50/50 chance something aftermarket will be feeding off the OBD port 12V power. As soon as I remove this, the PCM reads and writes fine.
Just an FYI...
2009.5 PBM G8 GXP M6 W/Roof-Self tune, OBX LTs, Kooks axleback, LSA blower, cam,
Monster LT1-SC clutch, flex fuel, 12 psi [email protected] 1,800 D.A
2007 TBSS-Self tune, bolt ons [email protected], 1,900 D.A
1991 GMC Syclone- Self tune/catback 12.8@104, 4,200ft D.A
i have had this issue with my truck using efilive. i found that my " dorman " hvac control unit wiggs out the communication network and never gets a proper flash. my truck has the dual auto climate control. i would try removing the radio fuse and the hvac fuse from the underhood fuse box and try it again.
My 2005 gmc yukon 6.0 dbw will fail everytime with the aftermarket radio harness plugged in--- I pull the radio fuse before a flash and no more issues--- When it first started , I was having to disconnect bat for about an hr and reflash with fingers crossed...
Bringing this back up for those who also cuss because of this problem.
Taking some ideas I got from this thread, I've now successfully flashed a couple of these 03-06 trucks pulling these fuses and turning off high speed...
*ALL* SEO fuses need to be pulled. All of them.
*ALL* fuses related to the radio or radio amp.
*ALL* HVAC fuses also need to be pulled. I think this one was the ticket but still not sure.
There's about 6-7 fuses that need to be pulled. After doing so and going on low speed it seems to work now. However keep in mind these PCM's are still stupid sensitive to voltage fluctuations, even just a c-nt hair. So make sure the truck has a great battery and there is nothing pulling on it during a flash. Nothing at all. No stereo wiring, no fog lights, fans or anything else. Absolutely nothing needs to be pulling on the battery. It *ALL* needs to be disconnected to safely flash these POS computers.
Good day gents.
It's pitiful that you have to do that.
Did you get it figured out?
Ive wondered what is going on that HPT has so many issues with the P59.
Got a buddy that does a bunch of tuning and he has given up on the P59s. I went to his shop one day and we tried several different things. Pulling all the fuses was the only way to get it to cooperate besides using a bench harness.
But i can use my V2 and an Autocal, they read/write no problem with all the fuses in place. Its really weird.
I have never had a single problem with the GTO p59, even with the radio and other things powering up. Trucks I have done are a different story. It seems to always require pulling a radio fuse at minimum, sometimes even for just a calibration write. I would suggest the p59 itself is not actually the problem.
I tune a lot of P59 applications. My original MPVI seemed to handle them better than the 2, 2+ and 3 do. It's definitely a good idea to remove the radio fuse, SEO fuses and HVAC fuses. I tuned two P59 trucks Friday. One was no problem. The other required benchtop tuning. Seems like 1 out of 20 will not allow flashing in the vehicle.
ive got an 03 tahoe-
has to be bench tuned, it will fail otherwise.
it sucks, but, oh well