The Diesel Stop banner

1 - 9 of 9 Posts

·
Registered
Joined
·
116 Posts
Discussion Starter #1
Got a strange one here. My 7.3's speedo started bouncing around about 6 months ago, mainly when I hit a bump. Then stopped working altogether. Occassionally would come back on but bounce once again. I replaced my VSS and wiring harness on the rear differential. I butt spliced the harness to existing wiring. No dice, speedo still didn't work so I thought it was something else. Been dealing with this for 6 months determined to figure it out. I finally figured out (light bulb went on!!) that when the truck got wet the speedo worked...(Desert rain occasionally and washing it). Turns out that when the butt splice itself gets wet, not the sensor, the speedo works perfectly. Once it dries out, speedo stops working again. I dump a cup of water on the splice and speedo works yet again. I used heavy duty butt splices. Is there a resistance issue or something similiar going on that the water fixes?

Thanks

Jared
 

·
Premium Member
Joined
·
8,474 Posts
I'd get rid of the but splices and use solder and heat shrink to seal it up. There is a vendor that sells the connector for the VSS with a short pigtail. I know I have one sitting in my tool box waiting for me to get off of my duff and put it in. I also had a problem with the VSS that I just got solved.

Or you could rig up a drip can of water above the connection and have it drip on the connection as you drive. But refilling the can could be a problem every now and then.
 

·
Super Moderator
Joined
·
11,617 Posts
I butt spliced the harness to existing wiring.
When I read this line I knew this was going to be your problem before you even described your problem. NEVER use butt splices, they cause far more problems than they fix. Solder and shrink tubing is the only effective way to splice wires.
 

·
Registered
Joined
·
1,720 Posts

·
Super Moderator
Joined
·
11,617 Posts
I'd say that about ScotchLoks, but I use butt crimps all the time, and have very few problems from them. Maybe 2 failures in the past 25 years.
I won't use them at all.
 

·
Registered
Joined
·
116 Posts
Discussion Starter #6
Thanks guys' really appreciate your advice. Solder and heat shrink it is. Steve83, thanks for the graphic. And Bugman.....lol!
 

·
Registered
Joined
·
116 Posts
Discussion Starter #7
Finally got around to this and you guys were correct. While i was in there I found another butt splice so cut that out too. Solder and heat shrink and we're good, works. Thanks again.

Jared
 

·
Registered
Joined
·
116 Posts
Discussion Starter #9
Could have been both but definitely mine considering water made it work.
 
1 - 9 of 9 Posts
Top