I'm Stumped-Need Help ASAP

ctdiesel99

ctdiesel99

Comp Diesel Sponsor
Joined
Nov 23, 2008
Messages
2,789
I'm selling my truck tomorrow. The guy asked me to fix the rear speed sensor since my speedo hasn't worked in a little bit. So i went a bought a new one today, got it swapped in, and to start off it didn't work. After cycling the key a million times, the brake and abs light didn't stay on and the speedo/odometer worked perfect. Took it around the block about 1/2 mile and it was fine. So i hopped in tonight to get some food, and about 2 miles down the road, the lights popped back on and the speedo started floating. Got back, disconnected the batteries, re-connected them and after cycling the key another million times the lights finally stayed off. Took it for a drive and all was fine until the lights popped back on and the speedo started floating again. So what do i start looking into first? It was fixed for about 1.5 miles, but after that the abs/brake lights popped back on and the speedo started floating (before i swapped the sensor it just sat at 0mph all the time). Thanks in advance guys, like i said i'm stumped.
 
bump for exposure, need to get this figured out tonight if at all possible
 
check all the rear wiring good. Rocks will fly up and smash them and give you intermittent connections. Look very closely!
 
is it the same part number as the one on the differential or a different one? I just don't understand why it fixed it to begin with but after a couple of miles started actin screwy again??
 
duallyspeed said:
Try the speed sensor on the outside of the tranny.
Click to expand...

99.9% of the time that being bad will cause erratic shifting along with loss of speedo. I believe its in the wiring because he replaced the sensor and the brake ABS lights are coming on too and the trans sensor has nothing to do with ABS and brake lights.
 
i think it's probably something in the wiring too, but i FUGGING HATE WIRING, and would have no clue as where to even begin diagnosing it. damnit man!!!
 
start at the rear axle sensor and I bet by the time you get to the fuel tank you will solve it. Look for knicks in the wire cover. If you can have someone sit in the truck running and watch the brake light while you wiggle the wires. Simple cut and splice will fix it up.
 
thanks chris, i'll head out there now and see what i can figure out.
 
CSnyder said:
99.9% of the time that being bad will cause erratic shifting along with loss of speedo. I believe its in the wiring because he replaced the sensor and the brake ABS lights are coming on too and the trans sensor has nothing to do with ABS and brake lights.
Click to expand...

You may be on to something.However abs/brake light could be a few different problems,maybe not in this case.My truck likes to wreck at least 3 things at a time.
 
Yep everything happens in 3's they say! He did say they come and go with the speedo though.
 
Try the tranny speed sensor, for $17 its worth it. Fixed my ABS/brake light and speedo. Autozone part #SU1034 When I went to the counter they tried selling me the axle sensor, so at least you can see what it looks like, for a auto.
 
mine's a 5 speed. and mark, just time to move on to something else. Lookin at a 12 valve in Ohio tomorrow night.

I went and checked the wires. There is a spot in the wire, where the wire loom is split in half and you can see the two wires that go into the rear speed sensor. The two wires are twisted together, but from what i can tell neither of the wires are split. Not sure what to do at this point.
 
ctdiesel99 said:
mine's a 5 speed. and mark, just time to move on to something else. Lookin at a 12 valve in Ohio tomorrow night.

I went and checked the wires. There is a spot in the wire, where the wire loom is split in half and you can see the two wires that go into the rear speed sensor. The two wires are twisted together, but from what i can tell neither of the wires are split. Not sure what to do at this point.
Click to expand...

If it were me.I would get a price on the speed sensor wire harness then take that off the selling price and let him deal with it.
 
I had a similar problem on my 01, turns out a stick knocked around one of my abs sensors on the front axle while driving through the pasture, busted it loose and it rubbed through on the rim... Replaced it and away the problem went.
 
You must log in or register to reply here.
Back
Top