App 1&2 correlation

So I just thought I'd share I recently had a jeep towed into my shop with no response from the accelerator pedal. The truck had been to another shop that had a parts shot gun. it had a new accelerator pedal and electronic throttle body assembly installed (bet that wasn't cheap...)
A quick look at the data and I really thought the problem was with app2

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Clear the codes and throttle would work till wide open throttle

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I don't have a pic of the scope I did screen shot it on my scanner I'll load it later but it didn't show all the dropouts on app2 like the data stream did (I'm not sure what that's all about) the problem ended up being the 5v ref line to app1 only had 4.6volts so at wide open throttle it would be to much of a difference in correlation verrified 5v at pcm Mitchell diagram showed a connector c104 on the diagram but I couldn't find where they listed its location (maybe someone can help me out with where to find that info in Mitchell or alldata) so i had to find it the old fashioned way with the scope hooked up at the app and perform the wiggle test luckily it was easy enough to get to after removing inner fender well after all the wiring was repaired it all looked perfect on the scope but when I loaded data stream the scanner still showed app2 dropping to 0v every second or 2 but no drivability issues so the moral of this I guess is don't get hung up on the scan tool showing dropouts in the app get the scope out and check it.

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Way to not load up the parts shotgun. :silly: Probably would have gotten an PCM at another shop.

I'm pretty sure that dropout on APP2 is normal (as you figured out). The PCM will drop the APP2 signal to ground regularly. It's a signal circuit integrity check, to make sure that APP1 and APP2 aren't shorted together. If APP1 starts showing the dropouts, the PCM knows there's a problem.

That's peculiar because I didn't see these same dropouts on the scope? I did see a couple small drops over a long time period but nothing like i seen in scan data I'll load the screenshots from the scope when I get a chance

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Peak detect might have picked the dropouts up but that isn't a normal scope setup unless some glitch is already suspected,

Good work