Well....

Swapped the VSS for a new one from Ford. In the process broke the clips off the original connector so I picked one up from O'Reilly's and splice it in properly. Changed the gear oil in the rear diff, THAT was way overdue good God. Buttoned it all back up, filled up the diff, took it for a test drive this morning aaaaand - nothing.

ABS light, OD flashing, no speedo, and no cruise. Tried running the harness up to the firewall as suggested earlier and I couldn't find any issues - even the convoluted tubing is still in good shape.

Only other thing I can think of right now is I may have spliced in the new connector backwards, but would that even matter? The new connector wires are both white, no identifying marks, so I hooked the left side up to red and the right side to green (OEM orientation in the original Ford connector).

 

It must be in the wiring or the VVS is bad. That's what happen when mine went out, no speedo, cruise & OD light flashing.,

 

VSS is brand new Ford-sourced. This only started happening after the flood waters. First the ABS went south, then the speedo started acting up two days later before finally quitting altogether. Wiring looks to be intact, haven't had time to probe terminals and wires fully yet.

 

mine went out again with the rain every day for the past 2 weeks, then yesterday it started working again after 2 days dry.
this morning it is raining, and it stopped working on the way to the store.

 

I finally fixed mine, had a separate thread in the Excursion forum.

Mine ended up being the ABS module itself. It receives and interprets the VSS signal before sending it to the speedo/odo. Based on where mine was (under the driver battery), I guess it got flooded out and shorted internally.

 

did you have to replace the entire ABS unit, or just the electric part?

 

Just the electronic module on the ABS pump.

https://www.ford-trucks.com/forums/1...l#post15444533 <-- should be the follow up post on my fix from the Excursion thread.

 

Welcome to my hell.....I had your symptoms and a bouncing tach as well...


Home Depot has nice tarps to cover the cab for when it rains.

 

Did this fix the issue?

 

no. one of the headlight modules broke a wire that was hitting the abs module, shorting it out. it finally burned out and i had to replace the module.

 

Wow Tom, so yours was way different than mine shorting from flooding... That's nuts that a broken wire shorted it and caused all kinds of chaos!

 

yea, it drove ne nuts for a while. i only found it when i realized the driver side headlight was not working.
when i pulled it apart there was a burn mark on the ABS module from the wire arcing against it.
and that also explained the intermittent work/ no work.
after i fixed it i realized it would only screw up when the headlights were on.

 

Mine was acting up, just had a shop look at it and they think it is the module but it stopped doing it the last 2 days they had it and so i took it back and it hasn't done anything since.