khsonic03

Hi All,

Just activated my account on this site today but wanted to give everyone a DIY on rebuilding your ABS module since I couldn't find this info anywhere on an F150 site when initially searching.

A quick description of the problem:

My truck (2000 F150 5.4L) had 150,000 miles when this first happened. I was driving from Connecticut to Florida and towards the end of the trip during one of the rest stops, I noticed that my ABS pump was running and wouldn't shut off, even when I turned off the car. I ended up removing the 50amp ABS pump fuse (#102) which temporarily solved the problem. The only downside is that this leaves you with no ABS (but I drove another 4000 miles this way with no issues).

After procrastinating this long, I decided that I didn't want to stare at my ABS dash light any longer so I started doing some research to no avail. No one had a DIY for rebuilding modules, despite the fact that plenty of companies will rebuild your ABS Module for about $150-200. Me being a cheapskate and an avid DIYer, decided to do it myself.

Please see the steps and pictures in the following posts:

khsonic03

Remove the ABS Module. For me, this sounded alot easier than it ended up being...

You will need to remove your air filter housing to have clear access to the module. It is approximately located under the Brake Fluid Reservoir.

Make sure to disconnect your negative battery terminal. There is 50amps that runs through one of the module connections.

Unscrew the 4 screws that hold the module on the ABS pump/housing with a torx bit. Please note that your ABS pump is directly under the ABS module and there is a harness that connects to it. You will also need to remove the harness on the rear of the module.

I had issues because my truck has 150,000 miles of Connecticut corrosion on it. Only one of the screws actually came off for me. The rest had to be removed with a cutting wheel and a dremel.

For future reference, these screws are M4 x 25mm. I bought some stainless steel ones with washers since all mine were ruined.

ALSO: You CAN drive without the ABS module in place - just make sure you pull the fuse and cover up the harnesses with some tape so debris doesn't get in them. If you do this, you WONT have ABS (obviously).

khsonic03

Cut it open.

Cut along the seam with a dremel cutting wheel made for plastic. BE CAREFUL not to cut too deep!! Only cut the minimal amount of plastic necessary to get through the housing. Don't bother trying to use a razor blade or anything else to get through...it won't work. You will need a small hack saw or a dremel to cut through.

Sorry, no pics of the process, but you can see the final outcome below.

Once you have the two halves apart, you can start getting to work.

There is a MOSFET chip that goes bad on this control unit in which the Gate burns out and is left in an open state, thus allowing power to continously go to the ABS pump. This chip needs to be replaced with a new one. This took me a bit of research to determine which chip to replace it with, but lucky for you, I will tell you exactly what part number you need!

Can you spot the faulty component in the picture? (If you can't, don't bother taking on this project)

khsonic03

Here's all the stuff you need, as well as some useful links.

OK, lets start with the MOSFET chip. The original chip that was installed is no longer produced AND was replaced with a new (better) version. Kinda makes you wonder if that's why the original chip died to begin with...

The original part number is:

SUB75N06-08 which is made by Vishay. Per their website, they replaced that chip with:

SUM90N06-4M4P (this is the one you want)

Here is a link to the chip on the site you can get it from (for a whopping $3.59)

http://search.digikey.com/us/en/prod...3CT-ND/2442169


Here is some MOSFET Soldering and info:

http://forums.xbox-experts.com/viewtopic.php?f=6&t=538


Aside from the actual chip (which is the only part that you need to replace), you will need:

MOSFET Chip
Arctic Alumina Thermal Adhesive (NOT Paste)
Solder (1mm Lead-based solder is probably best)
High-Wattage Soldering Iron
Flux
Solder Wick (to remove old solder)
Dremel Tool
4 M4 x 25mm Screws (preferable stainless)
Silicone Caulk
1 small piece of ABS plastic or other sheet of plastic
Rubbing alcohol and Q-tips


All in all, depending on what you already have, the cost to do this project is about $15-20 in materials. I will assume that most people have a soldering iron and dremel.

khsonic03

Remove the old chip and put in the new one.

Here is where you do the actual surgery.

1. Scrape off the protective coating that appears burnt in the picture.
2. Remove the Chip. You will need to remove the old chip by applying heat with the solder tip and using the solder wick to wick away the old solder.
3. Clean up the contacts by removing more solder, then apply flux to all the contacts.
4. Cut a small square on the backside of the ABS Module that is directly over the MOSFET chip (see picture). This will allow you to access the heatsink on the opposite side. You need to clean off the heatsink and remove any old thermal adhesive.
5. Solder in the new chip (sorry but I'm not going to explain how to solder).
6. Mix up the thermal adhesive and apply it to the heatsink, then attach it to the backside of the MOSFET chip and clamp it down LIGHTLY for about 5 minutes.

khsonic03

A few more pics.

khsonic03

Button it all up and reinstall.

See above pic for the piece of ABS I cut out and used to seal up the square hole I cut for the heatsink access.

1. Use silicone to re-adhere the square piece and the cover. Allow to dry.

2. Reinstall the module the same way you removed it.

3. Be sure to reinstall the fuse and re-attach the negative battery terminal.


At this point, you can fire back up the truck and your ABS light should turn off. And your ABS pump shouldn't be running.

I have a good code reader and was able to get the ABS codes that were stored and I had:

C1096
B1676
C1185

I cleared the codes and will check again in a few weeks, but they should be gone. Besides, the ABS light WONT shut off until all ABS issues are fixed (even if you clear the codes, the ABS does a self check when you start the vehicle and the ABS light will come back on)


As a final note, I AM NOT RESPONSIBLE FOR ANY DAMAGE OR INJURY YOU MAY CAUSE TO YOURSELF OR YOUR VEHICLE. YOU PERFORM ALL THE PRECEDING STEPS AT YOUR OWN RISK.


Please let me know if you have any questions - I'd be glad to clarify or help...

khsonic03

In the fuse pic, its the one in the upper right hand corner (50amp red).

The second pic is the whole underside of the ABS module prior to surgery.

Chris Maddox

First off, thank you khsonic03! I have a 2000 F150 4x4 offroad series with 163k on her. About two weeks ago I was in town with the truck and when I left the store I noticed my abs light was on. A little frustrated but not too worried about safety (being that only my anti lock brakes wouldnt work) I headed home. When I turned off the truck and got out I noticed a loud humming / buzzing comming from under the hood! I popped the hood and realized that my abs pump was continuously running, so I pulled fuse 102 and started doing some research. After running around in maintenance manuals and forums I figured it was most likely my control module. At that point it was time to start seeing how much these bad boys go for. Well...for a rebuilt module I was looking around 200+! For a used module with pump on ebay I was looking about 250+ and no telling how long that one would last. So, I found this forum and read up on what to do. I have always been an big DIY guy so this was definately the place for me. I opened up my control module without the dremel. Here's what I ended up doing: The control module halves are sealed with a pro-seal type sealant which is very tough and they definately did a good job sealing it together! I used a flat tip screw driver and an old dental scraper to work the sealant out. I chipped some of the plastic off in the process, but it wasnt much and not very critical. After that, I used the dremel to cut out the square on the back side to access the heat sink as shown in the picture. BE CAREFUL when cutting because there are parts that you can cut into on the board if you cut too deep! Once that was done I used an exacto knife the cut away as much of the thermal adhesive as I could and then I used some pressure and popped off the heat sink. You need to be careful during this process because you dont want to damage the pads on the circuit board. I then wicked away the solder from the mofset chip and heated it up enough to get it off. One problem I ran into was that some of the thermal adhesive had contacted the gate side of the chip, and when I went to remove the chip it tore part of the gate pad...(fortunately it still worked). Now, in khsonic03's picture it shows the MOFSET chip burned like a damn torch....however, mine looked completely fine as if nothing had gone wrong. I figured $3.59 was worth a shot anyways. I replaced the chip and glued to heat sink back on. I ended up using some heavy duty urethane to glue the module halves back together. I plugged the module back in and started it up. I still had the abs light on, but the pump was no longer running. I shut down the truck and started it back up again. The abs light went out and it's been working ever since (for about 5 days now). If you have this problem, it's a good bet that your abs control module MOFSET chip is bad. It really helps if you have a decent soldering iron for this job. I purchased a decent off brand solder station that had gotten good reviews and it work great. I spent 40 on the soldering station and about 35 on all the parts to fix the module. The mounting hardware is not that great so I also replaced that as well. I did the job without removing the air intake, but it would have been easier if I had removed it. Either way it's possible to do. I figured since I'll be heading to CO this winter, ABS would probably be helpful! On a side note, since I had a good soldering station now, I was having another problem with my odometer being intermittent. I removed my instrument panel circuit board and re-flowed all of the solder points for the connectors on the back (after hearing that there was a problem with cracks in the solder causing this problem). Everything now works like a charm and I probably saved around $1200 if I had replaced everything with new parts from ford! Time to take the family out to eat now and enjoy the savings!! LOL If anyone has these same issues and you have questions please feel free to ask.

khsonic03

Chris - glad to hear this worked for you. I had a hell of a time trying to find info on this when I encountered the problem.

My only concern is the urethane glue you used for the heatsink. The thermal adhesive is designed to specifically transfer heat to the heatsink, and since this MOSFET chip transfers a significant amount of current through it, it can get pretty hot (which is ultimately what kills the chip). However, since the chip is only passing current when the ABS is activated, which is typically for short bursts, you may not have a problem, unless you live in a climate where the ABS is constantly being activated.

**EDIT**
I just realized I read your post too fast...looks like you used urethane to glue the actual module together...my bad!