Does anyone have or know of a good "how-to" or "write-up" or video on how to bleed the ABS module in our trucks?

@dmueller71 managed to find one a while back that he was going to post up here, but life has gotten in the way as it often does.

So, if you know of one, please link or attach it here. If you are interested in creating one, I am available to help in anyway I can. Be that formatting, editing or just a second set of eyes.

I am hoping to include it in the 7.3L PSD Tech Folder. I see the ABS module needing to be bled come up quite often, but nothing on how to accomplish this seemingly simple task.

Questions, concerns or comments can be posted here or sent to me via PM.

 

If I recall correctly, one has to bleed the brakes via normal procedure.....then use the Forscan 'ABS Service Bleed' function to purge the old brake fluid in the ABS system. Apparently, the ABS unit will retain the old brake fluid until electronically activated.

I found this...."The process is quite straightforward: each circuit is bled as per normal in the order furthest-to-nearest from the ABS pump i.e. rear right, front left, rear left, front right. I used one-man bleed kits and the brake pedal. I then connected one bleed pipe to each of the front brakes and loosened the front bleed nipples. Following the instructions in Forscan for the ABS Service Bleed 'replaced fluid' option the ABS pumps and valves were operated by Forscan for ~20s pumping new fluid through the ABS pump to the brakes. This new fluid is fed by the reservoir and so make sure you keep it topped up!" source

 

+2. I tried the pedal pumping, gravity bleeding and priming pump method on my X and it never worked, I had to take it to a shop that had the Scan tool capable of doing the ABS bleed procedure. I dont lnow of any other way the DIY can do it.

 

If you do a normal brake flush then go activate the ABS a few times, slick or gravely road or on jack stands to save tire wear, I assume the old fluid would at least mix with the new. Not ideal, kinda like a drain & fill on an auto trans., but better than nothing.

 

Apparently, there is a "service procedure" in Forscan under the wrench icon on the left side. The information out there about this procedure is quite limited based on my searching.

@Stewart_H pasted a portion of a Ford technical manual that mentioned it several years ago. Although, I think during the time this was posted, Forscan was not readily available to the 7.3L community.

Mentioned here: https://www.ford-trucks.com/forums/1...procedure.html

Having the ability to bleed the ABS module via Forscan once the lines have been purged of air would be handy. I am still looking for more input or experience with this procedure. I will have some time this winter to look into how to accomplish this ABS bleed using Forscan, but would like to have something added to the 7.3L PSD Tech Folder before then.

I add things quite frequently. Just yesterday a diagram detailing the hydroboost system was added.

Thanks all, keep the ideas coming.

 

Yeah, if Forscan was available back in 2013 when I put that thread together, it just wasn't widely known yet. Other than the Snap-On units and AE, there wasn't much discussion on what could bleed the ABS system, and there was a growing "thought process" trucks equipped with ABS brakes couldn't be properly bled without bleeding the ABS too. I posted that info to refute that growing idea.

Stewart

 

Anyone else have a comment, suggestion or idea?

If not, this will go onto the back burner until things slow down a bit for me and I can get the truck in the garage for some testing with the Forscan Services area.

 

For most routine brake service, Stewart_H's write up covers it. Unless the ABS HCU was disturbed, air did not likely get in, and therefore bleeding with a scan tool is not likely to be necessary.

Brake component service at the wheel ends, and routine brake fluid changes, can be performed satisfactorily without fear of having not bled the ABS module.

Still, some folks may wish to bleed the ABS unit anyway, just for the fish. Likely the halibut.

If gathering ideas for a comprehensive addendum to the brake bleeding write up, then it should be noted that the '99 - '03 trucks deployed with two different ABS systems... RWABS (aka RABS), which is rear wheel only anti lock brakes... and 4WABS, which is four wheel antilock brakes. And even though marketed as four wheel, it was common for that system to only have 3 channels.

There are other distinctions based on production date... a big cut off date was November 30, 2000, where there is a service distinction between ABS systems of trucks built prior to that date are one way, and trucks built thereafter. A previous production transition date related to the brake system occurred in February of 1999. I am vague on recalling the details now, because well, that was 20 years ago. And in terms of just bleeding the ABS, as opposed to parts replacement, the production iterations won't make much of a difference. But people will like have questions about applicability, if they notice that they only have RABS, when a procedure is written for 4WABS.

I use the Hickok Instruments New Generation Star Ford factory scan tool (NGS) to bleed the ABS brakes. I guess that's cheating, but it pretty much takes the guess work out of the service. The NGS tells me when to step on the brake pedal, and then the NGS commands the valves in the ABS to open, tells me when to release the pedal, and also commands the ABS pump. If the folks at ForScan have managed to obtain the same factory proprietary service code and protocols as the NGS, then likely the $5 app will do the same thing as the NGS, which at one time cost dealerships $4,000 each during the era when these trucks were brand new.

 

I forgot to add that my X brake fluid drained completely when I swapped the rear axle, on the early 00 X and Super dutys they had driver side caliper in front of the axel and the passenger has it on the rear, and the later ones both have the calipers on the rear, just FYI so if someone planning on changing calipers or changing out the brake fluid "MAKE SURE THE BRAKE FLUID RESEVOIR DON'T GO EMPTY"

 

@z31freakify I recently did a front spring swap, new stainless lines, new front calipers and replaced the hard line from front to rear after it rusted out behind the fuel tank, all done on my 99 V10 F250. I bring this up because I was able to use my Lisle 46170 hood prop rod between the driver seat and brake pedal to hold the brake pedal down keeping the master cylinder reservoir full for a couple days as this was all done at home and waiting on parts. Keep in mind leaving the battery connected will drain as the brake lights will be constantly activated.

https://www.lislecorp.com/specialty-...p-with-support

I saw this tip on Eric The Car Guy's channel.

 

Nice Bently, its in the brain archives.

 

From another thread, Sous asked me to post this here. I’ve recently replaced 2 HCUs on different trucks, this is the test procedure for a leaking HCU on a 7.3 or 6.0

 

Thank you sir. I will get this added to the 7.3L PSD Tech Folder when I get to a PC.