Just went out for a drive, and the speedo bounced for a few seconds then just died, few minutes later or so "malfunction light comes on. Everything else is fine? 46k mile.
Anybody have any ideas?

 

Sorry.... 04 2500 hemi 4x4 QC...

 

i have had the same Issue with my 2002 1500 Quad. It was the VSS Sensor in the Rearend. It controls the Speedo and the ABS also. Swapped it out with a new one from Advance auto parts for $ 37.50 and disconnected the batt for 15 min. then went for a drive and was good as new..

P.S. With the Ram Rear End Issues , I'd suggest removing the Rear Cover and changing the fluid and Inspecting the Sensor from the Inside and Look for Metal Shavings all over it. It will be inline with the Exciter Ring inside the Housing.

Mine Broke this past weekend and Now Im looking for a new Rear End..

Rod

 

Do a search on here for speed sensor in the 3rd gen and see if that helps. Maybe reset the pcm?

 

so the vss is not an external sensor? also the ABS light never came on?

 

mounts to the upper rear axle housing

 

since the engine light came on, would a code reader trace the cause? Ive seen some other threads that seem to make me think if it was the sensor the ABS would come on?

 

There is a small electrical sensor on the very top of your diff.
Firstly, check that the connections in there are OK and that the continuity of all the electrical connections and electrical itegrety is good.
There's a little rubber seal running around the outside of the plug, which can perish/get damaged over time, letting in water/road grime etc.
Spray the crap out of it, then reconnect and do a PCM re-set and see if that cures it.
That's the simple thing to try.

Next, is to pull the sensor from the diff. There's a small bolt to remove with a metal clip which holds it in place. Remove that and try to gently pull the sensor out to inspect it.
If the round sensor is damaged/cut in anyway, you will have to pull the diff cover and inspect the toner ring and other internal stuff in the diff, to see if anything caused the sensor to become damaged. Typically, this can be the clutch pack retaining clip issue, these 1/2 ton 9.25 LSD ONLY diffs have (non LSD do not have this retaining clip problem). Or a toner ring problem/metal teeth chipped from the gear set's causing sensor damage.
Hope this helps?
Al.

 

Thanks for all the info, luckily its nice out, so Ill go for a climb under and see what I can find out with that info...
Thanks
Karl