Mechanics

ABS PUMP MOTOR RUNS CONTINUOUS EVEN WITH NO KEY IN IGNITION

Ford Expedition

2000 Ford Expedition 2 X 2 Eddie Bower 4.6L. I am trying to troubleshoot my ABS system. The ABS pump motor located under the air filter box will not shut off unless you unplug the motor or disconnect the battery. It began when I started the TK one morning and the ABS light came on and I could hear an electric motor running that I never noticed before. I drove down the road made a U turn and came back. I turned off the engine, got out and the motor was still running. No tapping, wiggling of wires or unplugging and reconnecting did any good. Any suggestions?
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GrindPopSnap
July 14, 2007.




What you are referencing is actually the air compressor for your air ride suspension. It will run if it senses that the vehicle is not even (the purpose being " even" for load hauling) and it can continue to run, if I remember correctly, up to 40 mins after shutting the vehicle off. You may want to have the air bags checked for a leak, or even the compressor itself (I had to replace mine about a month ago, with no problems since then), as it will continue to run like this until it eventually burns it itself out. If you want to shut the compressor off (although I wouldn't suggest driving it like this), the switch is located behind kick panel on the passengers side (not hard to find if you look, it is labeled). Hope this helps!
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Tiny
Jw_hanson
Aug 26, 2007.
Hanson is wrong, although his heart is in the right place. I have the EXACT same problem. The ABS module is directly below the air filter housing. The air compressor for the Air Suspension Unit is located in front of the battery (passenger side).

My ABS light came on a few months ago. I recently took it to have the ABS codes read at my local repair shop. They told me that it was the rear wheel sensor that was bad (located on top of the rear differential). After I got home and turned off the truck, I could hear something still running. I located the ABS-pump/motor under the air filter and could feel that it was 'operating' and pretty hot as well. I disconnected it to keep it from burning out. I replaced the rear wheel sensor, disconnected the battery to reset the system, then restarted the vehicle. The ABS pump still operates continuously (with or without the ignition on) and the ABS light is still illuminated. I am going to take it back to the shop tomorrow and have them reset the codes and re-scan them as well.

Let me know what happened with your situation!

Thanks!

Tiny
Musgrove10
Sep 17, 2007.
Any fix to this? Ours just started and I think I have narrowed it down to the relay.

Tiny
Biggone
Feb 21, 2008.
My solution was to replace the ABS computer module which is located on top of the ABS pump motor. Found one at a local salvage yard that was from a late model Ford truck. Apparently they used the same ABS control module/pump for many years in the early to mid 2000's. Cost was $100.00. They gave me the entire unit, which was the pump motor and the attached computer module. I removed the computer module and replaced it on my 2000 expedition (I believe it was 4-bolts) and all has been fine for over a year now. The original problem was the rear wheel sensor, which I replaced. However, when we originally ran the diagnostics to find out what what was wrong with the ABS system, something happened to the computer, which caused the pump motor to run continuously.

Apparently the most often component that goes bad on the Ford ABS system is the rear wheel sensor. I just happened to have the bad luck of also messing up the Control module(computer) when I had it scanned/tested.

Let me know if this helps.

Tiny
Musgrove10
Feb 21, 2008.
I just purchased a ABS Relay for the Motor Pump from Carquest at a cost of $90. I ran a scan on it and it came back as code free. I understand there is a ABS code reader also that might give me more results. For now I am trying to find out just where this relay goes in the car. I am going to be able to look at it more closely this weekend. If that doesn't work then I will do exactly what you did and replace the control module. I just didn't want to get into changing all the brake lines and rebleeding. It was one of the freak things that I went out to move the car into the driveway and when I shut the truck off and got out I heard the pump running. I had to pull the battery cable to get it to stop until I could locate the correct fuse to stop it. I didn't want it to burn up and didn't know how much time I had before it did. Thanks for the reply. I will let you know how it goes.

Tiny
Biggone
Feb 26, 2008.
You wont have to touch the brake lines at all. Simply remove the ABS computer from the top of the ABS pump motor control unit. It should be about 4 torx screws that hold it on the top of the main unit. Disconnect the wiring harness from the computer. Re-attach the new computer contol module and attach the wiring harness. No bleeding required (except possibly from your wallet). Only other advice is to disconnect the battery before - hand. I could attach a picture of the control module ect. If you need it.

Jason M.

Tiny
Musgrove10
Feb 26, 2008.
Thanks. I know where it is.I just haven't had time to get " into" it yet. Sounds a lot easier than I first thought. Maybe when I tear it out I will find that relay that I bought! Thanks again for your help.

Tiny
Biggone
Feb 27, 2008.
Just wanted to say thanks for your insight. I bought a ABS Pump Motor Relay, but couldn't find out where to replace it at. I ended up purchasing a Control Module just like you stated from the local salvage yard out of a 01. Plugged it up last night and it works like a charm. No lights and stops just fine (always a plus!) I took the relay back to Carquest and was refunded my $91. Best thing. The control module was under $50. Thanks again.

Tiny
Biggone
Apr 2, 2008.
Thanks for being there. Did a google search and found this site, and this is EXACTLY my problem. I'm a pretty good wrench turner (can overhaul etc.) But diagnostics is not my strong suit. I definately bookmarked this site. As long as I'm driving cars I'm afraid something will always be broke. Thanks again.

Tiny
Dailytrout
Jan 9, 2012.
@musgrove10, had this problem as well thanks for the advise, big help.

Tiny
Ajtallman
Aug 22, 2012.

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