I have a '99 Dodge Ram 1500 Laramie V-8. I have a check engine light on, ABS light on, speedometer is not working and neither is gas gauge. Also truck would not run without foot on gas. I have changed Air Intake control solenoid and the rear Diff speed sensor. Truck will now start and run however, still no speedometer and dash warning lights still on. What did I miss? Thank you in advance

 

Sounds like a good time to inspect the wiring all the way from the speed sensor forward. Grab the Factory Service Manual from the FAQ/DIY section for the schematics and connector locators. Crack open each connector, carefully to avoid breaking the old plastic, clean well, and reassemble with fresh dielectric grease as you go along. Continuity test everything with an ohmmeter (not a beeper!), too. Please report back afterward.

Might as well do the same for the gas gauge, too, all the way from the connector atop the tank forward.

Sounds a lot like some debris got kicked up and made a mess of things, if it all happened at once.

 

"I have a check engine light on, ABS light on, speedometer is not working"-I had these three things happen and I fixed each with the following:
1) As well as the engine light, my cruise control wasn't working. I found the vacuum line broken from dry rot at the 90° bend where it plugged into the CC servo. The cruise servo is under the battery. It cost $1.53 for the new vacuum line and I reused the fittings at both ends. It fixed the engine light and the cruise control.
2) The ABS/speed sensor in the rear differential was bad and replaced it-$20 from ebay. The ABS/brake light went off and it hasn't come back on and the speedometer works again.

 

He says he's already replaced his...

 

Just changed the Transmission output speed sensor also. Speedometer still not working, lights still on. Can not find any wires broken. Ill check the vaccum line though and thanks for the input.

 

ok still will not shift, all warning lights on as before. Now im told check tranny to change sensors in it. Any other thoughts as to what im missing? ECM was also changed with no better results.

 

Have you run what codes might be stored? If all the lights are on and they are on for a reason, then see what the codes are? ABS codes, CEL codes, or Body codes?

 

Do this and see what codes come up. https://dodgeforum.com/forum/2nd-gen...code-list.html

And when you replaced those electrical components, did you remove the negative battery cable while doing so? This will reset the PCM while you perform the work.

 

I know it sounds crazy but I would have actually checked to see what the check engine light was trying to tell me, by reading the code before just guessing and throwing parts at it.....

Thats just me though...
you might have somthing like a pcm fault and all this could be from a bad computer....

 

The hot ticket is to get the scan tool on there, note all of the failures it complains of, and find everything that's common to all of them. Chances are pretty good that there's one or more splice, power supply, and/or ground connection that's common to every darn one, and knowing which it is/they are can point the way forward.