2007 Silverado Classic

[DriverX]

Got the U7192 yesterday for my 2007 Silverado Classic Crew Cab 4.8L. This will be my second Diablo tuner, and fifth hand held tuner (not for the same vehicle of course). I have had excellent experience with my previous Diablo tuner, for my Mustang GT. Problem I am having with this current one is when I hook it up to the vehicle and proceed through the steps of the "Performance Tune" section, I get a message "Unable to read vehicle type (1)......."
I called Diablo this morning and Mike said to download the updated revision. I did that, and I get the same message. I searched through the forums and found a few possible causes. My battery voltage is good. I did remove the (3) fuses as stated in the instructions. Aftermarket radio faceplate is removed so it is inop. Aftermarket sound system is disconnected. I disconnected all aftermarket electrical accessories, with no luck.
When I proceed through the "Performance Tune" section, I notice my gauges will all fall to zero then back to normal, as if they are being reset. Is this a electrical issue? Or do I need to reflash my PCM?
I live in Vegas, and it is hot outside... and I just want to install the tune so I can play around with my truck again and not be pissed that I can't get it to work!!

[DriverX]

I am getting my truck's PCM reflashed at the dealer later. Hopefully this will help. I have spent the last two days pondering my purchase of this product, as I have never had this problem with any other handheld tuner. Hopefully it works tomorrow...

[DriverX]

Got my truck back from the dealer... looks like they were unable to communicate with the vehicle as well. They believe the PCM is bad. I am still able to drive my truck though! Dropping the truck off again on Monday and hopefully they can figure something out and fix it because like everyone else here, I bought my truck to drive it... not to sit in a service bay.

[pheonix311]

wait......you have a bad PCM yet can still drive it?!

in a nerdy nothing ever works for me like that way thats awesome, ive never heard of a vehicle being operational with a dead computer component

[CANUCKPREDATOR]

may be just the cabling to the PCM. if PCM was major screwed, truck wouldn't run.

[Mistic]

Not true....it very well can be just the PCM as opposed to wiring. My wifes Grand-Am had a pcm go bad in her car and everything functioned perfect exact for at a certain RPM the car would shutter and the tach would jump about 5K. I brought it to the dealer ship and they told me that a portion of the PCM memory became corrupt. I installed a new unit, had it flashed and it was as good as new.

Apparently a PCM is like a computer hard drive.....if the right area is corrupt the unit will not complete crash because the main operating system may not have been damaged but maybe just some of the drivers.

[DriverX]

Yea, my truck runs fine. Weird though that it would still function as if everything were normal. The dealer was having a hard time trying to read the PCM. They thought it was the Tech2, then they thought it was TIS.... but everything on their end seemed to be working fine. Trying to schedule another appointment for this week so they can replace the PCM under warranty. This really sucks because I wanted to play with the tuner over the weekend. I will post with results, hopefully I will get this resolved this week.