The ABS light on my '98 Expedition EB (5.4L) is on. Before it turned on, I replaced the front pads and found some wear on the inside surface of the left rotor. I should say the wear is a little bit deeper than I am happy with. I may replace it soon.

I have 2 question for your experts here:

1. Is this ABS light on condition caused by the rotor wear or anything I did?

2. How to get the ABS code out of this truck? Do you have any code scanner recommendation? I do have an OBD II code scanner for this truck but it can't read any ABS code.

Thanks alot!

WhyFord

 

The ABS light can come on if the speed sensor is not working. Also there is an exciter ring on the inside of the rotors that a hall effect sensor picks up wheel speed on on. If you removed or bent that ring or sensor it could cause problems.

I got a code scanner from Autozone for $150. It reads and resets codes but will not run diag tests. Its the best money I ever spent. It has saved me and my friends hundreds of dollars, along with the helpful folks at this site.

You can also clear the codes by disconnecting the battery for a few seconds.

 

Thanks for the information. I will check those sensors and rings this weekend.

About the code reader, can yours check ABS code? I got mine also at AutoZone for $149, but it can only read and eliminate engine code. The ABS read out is from a seperate connector and this one I have can't plug on to it. Any more information on this?

Thanks again.

WhyFord
'98 Expedition EB, 5.4L
'94 Bronco XLT, 5.8L

 

An easy way to check if the ABS sensor is the culprit is to do the following:

1)start your truck. Does the ABS light stay on after the initial light up? If it does, then this fix probably won't help. If it goes off, go to step 2

2) Put it in drive. Scoot forward a few feet. Does the light come on once you start moving? If so, then it's probably the ABS speed sensor ($13 at the dealership).

You might as well replace the speed sensor anyway - if your whole ABS system deep-sixed itself, it costs some ungodly amount of money anyway, so go ahead and spend the $13 to replace the sensor (it's located on top of the rear differential, facing towards the front of the truck.

Good luck - let us know how it turns out!

XXL

 

When I first start the truck, the ABS light is not on. It turned on only after driving forward for a minute or two. But I don't think the speed sensor on the differential is at fault because the one on my Bronco was broken once and I know once it's gone, it will give you three symptoms simultaneously:

1) The odometer stops working (because there is no speed signal);
2) The transmission shifts rough (because it doesn't know what speed to shift without the speed sensor);
3) The ABS light is on (because ABS system needs vehicle speed to compare with wheel rotation to determine if the wheel is spinning).

But on my Expedition, I only have the last symptom.

Therefore, I didn't buy that speed sensor at the dealer (it costs $17 now instead of $13). I did check the price of the ABS sensor at the dealer and it costs about $30.

What I will do next (when I find some time) is to take off the worn out rotor and check the ABS sensor and that ring the other guy suggested. I think the metal debris from the excess wear last time probably messed up that ring or contaminated the sensor.

Any special tools, tricks, or suggestions you have on taking off the rotor?

Thanks a lot and I will have you posted on this.

 

I was wondering if you were able to fix your ABS Light on problem?

I own a 2000 Expedition EB 5.4L and my ABS light all of sudden turned on. When you turn on the vehicle the ABS light remains lit. What can this be? I was reading the threads and changing the ABS speed sensor might fix but I would like to know if you tried this. Any feedback would be helpful.

Thanks.

 

Since your ABS light turns on as soon as you turn on the truck, I think you have a different kind of problem than mine (I have to drive forward for a minute or two in order to turn on the ABS light). I believe you have a discontinuity somewhere on the ABS senser line, either a broken wire or disconnect internally. I think the ABS computer can only tell this kind of problem before the truck moves and then turn on the light.

Last weekend, I checked the ABS sensor on the worn rotor side. I was right, the sensor was covered with metal debris. Because the tip of this sensor is a magnet, it attracted lots of metal debris from the worn rotor to it. The metal debris also covered some of the exciter ring on the inside of the rotor. So I thoroughly cleaned both the sensor and the exciter ring and thought I fixed the problem. But amazingly enough, the ABS light turns on again!

My next step will be disconnect the ABS sensor on this wheel (maybe all wheels) and check its resistance. By comparing their resistances, I may be able to find which one is abnormal and then replace it.

I keep asking who knows an ABS code reader that can read the ABS code from this truck, but nobody responded directly to it. If I had such a code reader, then it would tell me exactly what is wrong with any part of this ABS system.

I will post a message once I fix the problem to close this thread.

Thanks!

 

The ABS light on My wife's 2000 EB Expedition (62K miles) came on yesterday. I seached on Yahoo [Ford and Expedition and "ABS light"] which led me here.

I changed her rear-differential speed sensor with the one from my 2001 F-150 SuperCrew and it fixed the problem! Although I now have the same problem on my SuperCrew until I can get a replacement.

Thanks for all the help and maybe this will help someone else.

Details:
I found that when you turn the key to run position, the ABS light comes on with all the other lights, then goes out, you hear a quick vibration form the ABS Module (near the master cylinder), and the light comes back on and stays on.

The quick vibration is apparantly the ABS self test during initial startup. If you hold your foot on the brake while turning the key to run, the ABS light will not come on until you release the brake. Apparently, the self test does not happen until you release the break pedal.

First I cleaned the wheel sensors on the front rotors; they were filthy, but that didn't solve my problem. Then I went to AutoZone to buy a rear-diff. speed sensor; they didn't have it so I bought a Haynes manual instead. It talked about the brake-light on/off (BOO) switch. I disconnected the BOO and the ABS light did not come on! I thought I was on to something so I tested the switch and it was working perfectly.

The only thing I had left before going to the dealer was to replace speed sensor and that saved me the trip and the bill! I guess when it didn't get a reading from the speed sensor during self test, it disabled the system and gave the warning light.

Thanks everybody!

 

By hint from P-Bod, I did the same thing: swapped the speed sensors on my Expedition with the one on my Bronco and I fixed the ABS light problem on my Expedition too!

BigMattXXL first suggested this speed sensor problem but I didn't follow because I replaced the one on my '94 Bronco once and I knew it caused me more problems than just the ABS light (I lost odometer reading and smooth transmission shift altogether). Now I know Ford must have changed their design from '94 to '98 so this speed sensor on the differential doesn't send signals to the odometer and transmission controller anymore (they must have another speed sensor for that now). I just bought one ($17) for my '98 Expedition and found it's exactly the same part number as the one on my '94 Bronco.

Well, thanks to everyone participating in this discussion and we have more than one happy drivers after all!

 

I have a '99 expy with the same ABS light problem....comes and then goes off when cranked, but comes back on after the truck moves a little. To replace the speed sensor on the rear diff., do I have to open up the rear diff. or can I just remove the bolt that holds the speed sensor to the top of the rear diff?

Thanks

 

The easiest thing to do is back it up on ramps (optional - I'm a big guy), take out the spare tire (also probably optional, but gives you way more room to work), sit indian style, facing the differential. The sensor is on the top, on the opposite side - a mirror helps a lot. I believe the bolt is 5/8" (I'm not sure though - I'm a big fan of metric. Can't remember the standards )

Easy job to do, inexpensive part.

Take care!

XXL