vss nightmare

[08twinturbo]

Hey guys. I read and read. Found a ton of info on it. Here's the deal. 2005 f 350 Truck comes in with no speedometer. And low power at wot. Check codes. Find p0500. That's it. Trucks runs and drives flawlessly. Other than the fact that the ENGINE ONLY TRACTION CONTROL is engaging because pcm has no vss signal. Found this in ford service manual. So I have this high dollar snap on tool that scans all modules in the truck. Abs module has no codes. And I can read speed from the front 2 sensors and the one rear sensor at the abs module but the abs has 0 vss output to pcm. What is the next step to confirm abs module is bad with it having no codes? Before letting dealer do their tests. Any help is appreciated.

 

[suprdzlduty]

Had this issue on one also...it needed a new module. It didn't throw any codes for me either.

 

[08twinturbo]

Thanks for the help. I was sure that's what it needed too. But today I looked at the wiring diagram and found that the vss feeds the radio. Guess what? Someone has installed a aftermarket head unit. So I pulled it out and they had cut wire harness in half and then taped each wire together. No connectors at all. Vss wire was hanging and touching frame.I redid harness and she works great again. Full power is back. Absolutely amazing.

 

[diesel slacker]

I'm dealing with this exact problem at the moment. Also mine has a problem with an erratic input shaft speed hanging around 10,000 rpm.