I've got a 2000 XLT 4.0 2WD automatic w/ 94.5K miles. All stock, other than a bed liner and cap. It's very clean and generally runs really well. I've kept up with the oil changes and inspections.

Work other than maintenance has mostly been brakes (it seems to go through pads and shoes a little on the fast side - must be my driving habits), although a few months back, the check engine light came on steady, and the mechanic deduced there was a vacuum leak in the intake head gasket, and replaced it. (His prices were a bit steep, so I'm not enthusiastic about going back to him.)

Starting a couple months after that, the check engine light occasionally came back on for a few days, then went out again for a couple weeks. Then it stayed off for a few months. While it was on, I had the codes pulled, and it reported a problem with an air sensor (I don't remember off the top of my head). But the performance didn't appear to be affected, and I let it slide.

All this is leading up to this afternoon. I left my office to go to lunch and noticed the ABS light was on. Then I noticed the speedometer wasn't registering. I came to a stop light, killed the engine and restarted, and the ABS light briefly went out but then returned. When the light turned green and I pulled away, the speedometer still wasn't moving.
And then the check engine light came on.

Braking appears to be fine, although not as crisp as when brand new shoes and pads have been installed. And again the engine performance doesn't seem to be affected. I haven't had a chance to get the codes pulled yet.

With all this happening simultaneously, I'm almost suspecting the instrument panel connections, but as far as I know, there's never been any work been done near them.

Any thoughts on something that might cause all these seemingly unrelated events to happen simultaneously?

- John

 

There's a sensor on the rear axle that sends a signal to both the ABS and speedometer. That's where I'd start.

 

things are not
easy like they used to be

 

Golddirt, you're right, and to think that when I was a teenager I knew it all

 

My ABS light has been on for around three years now ever since I slid into a curb when coming to a stop at a Michigan winter intersection. Brakes still work ok although alittle vibration is felt when braking. I saw you mentioned the abs sensor located on the rear differential. If I replace the sensor (only 13.99 Auto zone) will my problem be solved?

 

Thanks to this forum I discovered free code pulling at AutoZone stores. Greg R was correct. The code was P0500. The print out says:
I'm relieved to find that it's nothing more serious. I'll just use some duct tape to fix it. One piece ought to cover those lights. Who needs a speedometer anyway. [just kidding]

So, I can see the connector on the top of the differential. I'm assuming that's the speed sensor. I'll check that plug to make sure it's got a good connection. How about the other end of the wires? Where are they? Hopefully that's the problem, but I can replace the sensor if necessary. (Not sure what to do if it's a "Drive gear mechanical fault" though.)

I just called NAPA and asked for a price on the vehicle speed sensor and was told they don't have listing for that part. I suggested it may be listed under ABS sensor, and they didn't have that either. What's the official name for this thing?

- John

 

VSS is very easy to check if you have o-scope. Else try and try way is used.
1. Check connector (it may be corrosed)
2. Check and repare wiring if neccery
3. if nothin helps, change VSS

 

My ABS light kept coming on so I drained 1/2 my rear diff and added Ford limited slip additive and topped up the gear oil and it has not come on since, I think there was a build up on the abs sensor on the diff.

 

I got a new sensor from NAPA and swapped it on Saturday. That solved it.

It took no time at all to replace the sensor, but then the wire connector didn't seem to fit. It would only go on part way, as if the pins weren't aligned. I spent maybe a half an hour trying to get the damn plug on securely, even trying to bend the pins slightly, but nothing worked. Then, while inspecting with a mirror, I noticed that the shell of the plug was hitting the body of the sensor. I grabbed the old sensor and noticed it was notched to allow the connector shell to slide in further. The new sensor was missing this notch. I ended up cutting away the connector shell a little at a time until I could push it in far enough for the clips to engage. Hopefully it's still sealed enough to keep water out. What a PITA. Keep this in mind if you have to replace one in the future.

Thanks to this forum and all the fine folks who contribute. I was debating canceling a weekend trip out of town when this first happened, but I didn't need to after all.

- John