PowerWagonCC80

My TPS is not working at all and I just replaced it a week ago. Can I by pass it by using a switch to turn on my O/D? Need help!!!

KRB

There's a sticky for putting in a pentometer and several other options including using other cheaper TPS.

I have a resistor in mine that works fine.

j_martin

Are you sure the TPS is bad? There's several other items that can keep it from going into OD, including temp sensors, TPS adjustment, PCM, and a multitude of connectors.

If the TPS is bad, There are options to install a direct switch to the OD, a potentiometer to manually select the shift point, a fifty cent pair of resistors to do the same, only not adjustable, and a couple of ways to mount a gasser TPS which costs about 15% as much as the OEM.

If the TPS isn't the problem, only the direct switch will help.

BTW, proper diagnostics, that is determining exactly what is wrong to start with, is the fastest and least expensive path to a repair.

Generally speaking, guessing and throwing parts at it is the slowest and most expensive path.

PowerWagonCC80

I know for a fact that's its my TPS. And if I replaced it, it would the three d time that I replaced. I"ve heard of guys putting a switch to by pass it and do away with the push button on the dash. It just seems easier to do it that way, I think. Its just needs to work for a couple more mouths untill I put a Getrag 360 in my truck to completely do away with the automatic.

PowerWagonCC80

If something was making my TPS to go out what or where or how would I see if there was something grounding or frying it?

j_martin

Try the resistor solution. If it works, you just got a JIB (junk in box) TPS.

It would take a combination of dead short to ground or 5V, combined with gross mis-adjustment to fry the TPS quickly. The design is flawed, with DC current through a moving potentiometer wiper, and that is what wipes them out in a year or 2.

PowerWagonCC80

Interesting...where can I find the material to build this contraption. So, when this is built I put it into the TPS and put a ground on one side and 5+ volts on the other? To test if it works?

j_martin

Those are commodity resistors, available at places like Radio Shack. Those particular gold plated solder cup pins are from a pile of old military surplus parts I have laying around. They happen to fit the TPS connector pretty good. You could probably just fold back the wires on the resistors to double the diameter and shove em in the connector.

It shoves into the TPS connector just like you see it displayed.

Before you get your knickers in a knot, you should back probe the tps connector when connected and verify 5V, 0V, and center terminal out of range and/or not varying with throttle movement.

If all the above is true, then disconnect the TPS and probe ohms from one end terminal to the center terminal and operate the throttle. It should sweep from about 1000 ohms to 3000 ohms, smoothly. The numbers aren't important, but the smooth sweep is. If that's OK, then there's a fault somewhere else in the circuit.

I probably have one of the resistor twins laying around if you need to borrow it. I've replaced both of mine with these:

https://www.dieseltruckresource.com/...stable-317923/