Major Passat GLX brake issue

We've been looking at new cars recently, and my longterm 94GLX must have noticed because a significant brake problem has cropped up.

Symptoms: Leaving work today, the Brake and ABS indicator lights lit upon ignition, but did not go out after a few seconds, as per normal. In addition, I had no airflow on the heater/AC controls whatsoever. Ok, I assume I can limp it the 3-4miles to the sitters to pick up the kids, and can deal with it after I get home a couple of miles beyond that. She wasn' going to let me off that easy.

After about two miles, the brakes started acting a bit funny. The firm pedal feel wasn't there, although a couple of applications would firm them up to brake properly. Within a half of a mile of the sitters, the brakes went really firm, as in rock hard, and stopping power was a mere fraction of normal. It was almost as if I had replaced the brake pads with greased blocks of wood. Scary, really scary.

I limped it to my sitters driveway and opened the hood for a look. Brake resovoir was full beyond the MAX level. Odd. I borrowed a straw and a screw top bottle from the sitters, and proceeded to get enough brake fluid out of the resovoir (about 3-4 ounces, as a guess) to bring the level down to MAX. I restarted the car, and the Brake and ABS indicator lights went out after a few seconds, as per normal. Proceeded to drive it around the block, and the brakes behaved as they should. Upon returning to the sitters, I popped the hood, and noticed the brake resovoir level was now around MIN. I added back about half of what I took out, to bring it between MIN and MAX, bolted the kids in, and carefully drove home without incident.

I called on old mechanic friend, who knows and understands German mechanicals, albeit mostly of the BMW variety, inside and out. He wasn't that familiar with the Passat, but upon mentioning that it had a brake accumulator system (as per my owner manual) he mentioned that BMW's use a similar system, and referred to it as a "brake bomb". A bit of Googling indicated he is not the only one. He also indicated that failure of such a device could yield the kind of symptoms (really hard brake, extra fluid in the resovoir, and indicator lights) that I had mentioned.

OK. Time to dig around on the net. My normal parts source (Germanautoparts.com) did not show an accumulator. A general Google search didn't help much either, although it did suggest that my 94 has a pretty complicated ABS braking system (by ATE?), and that most of the subassemblies are not available. A look at 1stVWParts, which I gather is a reputable Left Coast dealer of factory parts, did show an available accumulator, although not cheap. Still better than the complete master cylinder/ABS assembly, at over $1000. A thread at VWVortex, from somebody with a Corrado, indicated a method of checking the hydraulic pump, by bypassing the fusebox/relay panel, and appying

12V to the pump. He indicated his problem was fixed by replacing a number 78 relay, at less than $50. Tomorrow, I will try the pump check, and try to find the relay and see if that is bad.

My real questions are: (1) Has anyone seen anything like this and what did it take to corect, and (2) is there any kind of trouble shooting procedure to isolate what might be the culprit? Where to look for parts? Should I stick to dealer parts (1stVWparts?) or can I find something decent on the secondary marker or should if try for a junkyard complete brake master cylinder assembly. On the latter, anyone know of any reputable VW dismantlers that might have such an item? Is there anywhere I can find a proper schematic of the system, other than the dealer? Even though I don't trust dealer shop much, the service manager, who is a decent chap, might let me look at the old manuals, if they still have them.

I'm dealing with an 11+ year old car, and it doesn't make much sense to throw $1000+ at the problem. From past experience with my local dealer, I'm sure they would just advocate a complete ABS master cylinder and related hardware replacement.

A few years back, the dealer couldn't even find a major power draw that was eating batteries. I took it home, hooked my Fluke between the battery and the hot lead, and found a 5+Amp power drain, with no key in the ignition. Further, I found the power draw was not going through the fuse box. Upon checking the dealer electrical books, I found the safety systems did not go through the normal fuse panel, and isolated to problem to the right automated seatbelt assembly. The motor never shut off when the belt was retracted. Upon my findings, they finally replaceded the belt assembly, and gave me another new battery. I'm sure it was a fluke, but they just didn't seem that interested in deep trouble shooting. Quick replacement of possibly suspect subassemblies, especially if they kick a computer code, is more their forte. Thats fine, if you on a warranty, but its not going to work in this case.

If I can get a start, I will order some parts, and drop it in the lap of my BMW guy. He is the only guy, out of many, that has shown a real knack for fixing the unfixable. He saved an ex-boss of mine thousands of dollars, on an ABS repair of and Acura Legend, after tracing the fault to a crapped up connector. One dealer suggested replacing the whole ABS circuit, at over $2000, while another suggested disconnecting it. Joe charged him for 6 hours trouble shooting and sent him on his way. He also once talked me through a timing belt replacement, on an old 1980 Rabbit, correctly naming every size and type of wrench and socket needed to work me through the job, without taking the whole front end of the car apart, as per VW recommended practice. He is also a very cranky old fart...used to drive an old

1980's S-series MB, that he bought reasonable off a long time customer, with GRINCH for a plate. He said he would look at my Passat, although it would be helpful to know what was in there and what was available.

Yeah, it got kind of long winded. Sorry. I've had her since new, and I'm trying to stretch another year or two and 10,000 miles out of her, if she doesn't run me to the poorhouse first. At this point, its become somewhat of a grudge match. I'm sure others know what I'm talking about.

A huge thankds, if you've made it this far.

David Glos snipped-for-privacy@hotmail.com

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