Diagnosing speedo...

[BushWakr - RIP]

I had this problem last year... I put in a new VSS and all was good... . until this week.

I now have the same problem back again... this is gonna make me nuts... we gotta find the cause of the failure not just treat the symptom. .

Any of you electrical guru's out here have any thoughts on why they fail????



edit: I still have my old one around here somewere... I'm gonna dig it up and take it apart to look at the internals... maybe they can be hot-dog'd to work. .



pastor bob...

 

[Paychk]

PB



The sensor is solid state; when it is opened, it is FUBAR. The problem is there is two styles, two or three wire. The three wire is a Hall-effect type and needs an input voltage to work. The two wire I haven't a clue as to what process it uses to generate the on/off pulse just that it does. Evidently, the pulse is read independently by engine computer, Canadian DRL, and the speedometer. How does the DRL system work? Does it turn on all by itself when the truck starts moving? If so do your lights turn on, as they should?

 

[jwilmoth]

https://www.dodgeparts.com/oe_parts_catalog.html



Mine is works one day and not the next, These guys have it for $38. 00.

 

[Philip]

The two wire is for manual or 4X4 equipped trucks.

Some of the later 1st gen auto $X$ trucks might have the 3 wire VSS. My 93 does with a auto and $X$.

 

[Paychk]

Philip thanks for the info! I have no access to a $X$ so I was going by the manual.