What sets the Service Throttle Soon light?

[snarl95]

Left the house this morning and turned right onto the road. Drove two blocks and made a left. About 100 feet later the throttle pedal stopped working and the engine dropped to idle. Lucky it was still in high idle and I could get to the CVS parking lot. Shut the truck off, waited a minute and started the truck back up.Ran fine the rest of the day. Any help is appreciated.

 

[ak diesel driver]

There's 3 separate tps sensors in that throttle pedal assembly. IIRC the pcm wants to see 2 of them basically the same. Might be other things that will set the light too but I think this is the most common. I have similar issues when it gets cold until the cab warms up.

 

[Paveltolz]

Had the same issue. It was a glitch in the tune. Drove fine after doing the Key off, restart but, I bought a new PCM. I was able to get the box re-tuned since the tuner still had the program on file.