Hydraulic Control Module - Leaking?

[Off_Timing]

Hi Guys.

Our van : 2000 LX w/ 3.8L.

A couple of weeks ago, I topped up the brake fluid which was low. A couple of nights ago, I was crawling around under the van checking the exhaust system, when I noticed that the dust cover for the hydraulic control module was "sweating". It didn't smell like oil, so I'm assuming it's brake fluid. This morning, I checked the brake fluid, and it's noticeable that it's less than when I last topped it up.

Nope, I haven't read the ABS code, I don't have an ABS code reader. The yellow ABS light is on. I've assumed it was a sensor or exciter ring issue....could still be but the HCM needs attention also.

Before I bite off more than I can chew, does anyone have any advice as to what I can expect before I remove the dust cover?

I'm somewhat competent home mechanic, but I've never worked on the brake hydraulics before. Is this a DIY job, or something that should be left to a pro.

Does the fittings for this unit have a tendency to loosen or do they just go bad and need to be replaced?

Thanks.

[scubacat]

Better to pull that dust cover and see where the leak is coming from. It's just a few quick screws and it pops off easily. I wouldn't want to even guess at what's leaking without actually seeing it because it could be anything. That's not a routine failure item as far as I know.

[mark_gober]

Dust cover is simple to remove. If nothing else, you'll get your eyeballs on whats leaking. My guess is it's a leaking fitting. I'd try to tighten it and see whatcha get.

Good luck.

Mark

[12Ounce]

I agree, most likely leaking at a fitting ... which there are several, so get the flare-tube wrenches ready. The hydraulic controller itself is a fairly sealed-up black box ... and it sits atop a boiler-plate protective support bracket. I doubt if the unit itself is leaking ... but if you have bumped over some huge rocks or something... well, then its possible it has been cracked or something.

[phil-l]

I replaced the electronic portion of my ABS module on my 00 Windstar - and took pictures that will help you understand what you're seeing when you take off the cover:

http://good-times.webshots.com/album/575113025YrtncQ

[scubacat]

You lucky sucker. My studs were well-rusted into the HCU. I had to disconnect all the brake lines, pull down the whole stack, dremel off the top of the studs, lift off the EBCM, then grab the studs with vice-grips and twist them out. (one actually bent significantly before it finally gave way.)

Note that once you disconnect any of those brake lines you have to get the system bled and I had to (carefully) drive it to a shop to have that done since it has to be done by computer. (I saw a very lengthy process once to do it manually by shorting out a series of pins on that connector but I lost the link to the instructions.) Thus, if there's any way you can remove it like in the pics above, do it that way instead!

[12Ounce]

I have also replaced the electronic controller, with "trac-control", twice on my '99. Both times I just dropped the whole assembly ... so the fluid got dumped each time. There has never been an issue refilling the brake system with fluid and bleeding. Guess I was lucky.

BTW, the first replacement was with a new controller from Ford. The second time no new replacement was available ... so a reman was purchased from Ford ... and the old unit was needed for "core". Both times this controller has cost some major bucks ... several hundred as I recall.

[scubacat]

Originally Posted by 12Ounce

BTW, the first replacement was with a new controller from Ford. The second time no new replacement was available ... so a reman was purchased from Ford ... and the old unit was needed for "core". Both times this controller has cost some major bucks ... several hundred as I recall.

I took my dremel and carefully cut the plastic cover off just above the circuit board (just like in the pics above). I then desoldered and resoldered all the large solder joints. Once that cooled a bit, I covered them all with some a little conformal coating. Finally, I took some plastic epoxy and reattached the cover, hooked everything back up, and all has been well ever since (2+ years so far). The nice thing about just resoldering the bad joints is that you don't have to do any reprogramming of a replacement unit.

[phil-l]

Originally Posted by scubacat

The nice thing about just resoldering the bad joints is that you don't have to do any reprogramming of a replacement unit.

Quick note: I got my replacement module from Ford (specifically through the Team Ford Parts web site; I'm a pleased customer) and didn't have to do any reprogramming.

[Off_Timing]

Hi Guys,

Thanks for all the replies.

I did find the other posts about replacing the HCU and the electronic controller (and the subsequent re-programming).

I've taken the dust cover off and the HCU is pretty gunky. I carefully wiped down the unit and waiting a couple of days of use to see where the leak could be coming from.

I checked the brake lines, calipers, and other hyrdo components. No leaks, so I have to assume it's coming from the HCU. The fluid level hasn't gone down noticeably, so it must be a small leak. I'm hoping it is just a fitting.....it'll be a good excuse to buy a flaring tool.

Thanks. I'll post what I find.

[12Ounce]

I wonder if the leak is somewhere else totally .... a caliper leak can be awfully ellusive. I hate to see you put a lot of effort into the wrong area.

[12Ounce]

Perhaps a split tube ...??

[Off_Timing]

Hi Guys. Just thought I'd update the thread on the cause/solution to this problem.

I sent the van to my (trusted) mechanic. The leak was from the brake proportioning valve. My wife picked up (her) van and she said the brake pedal felt less spongy.

Thanks for all the input. They always save me from disassembling things I don't need to. :-)