Brake Misbehaviour - maybe not ABS?

Peter Berrevoets pjberr at
Sat Sep 8 16:09:46 EDT 2001

Thanks to those who responded earlier,

I finally pulled the fuse on the ABS and have had better, but not problem
free, brake behaviour.

After checking that the ABS fuse/relay was fully functional, that the
parking brake lever was fully seated, that brake fluid was topped up, I
pulled the fuse out.

I haven't checked the sensors on the wheels, or the pressure switch on the
hydraulic assist thingy, but I had this happen;
Drove for a while and the brakes worked great - without the ABS - noticed
that the fluid in the hydraulic reservoir had dropped to below the minimum
mark - bomb fully charging? - so I topped it up. The brake warning light
finally went out after about 10 minutes on the highway. A day later, after
great brakes and no warning light, I was in heavy traffic in town - stop and
go - lots of brake use. The pedal started to harden up and the light came
on. Upon visual inspecttion of the reservoir, it has filled itself right to
the top - bomb discharge? For two days now it has stayed like this, and I'm
wondering if it is the hydraulic brake assist thingy ot something to do with
the master cylinder. The ABS may have a problem relating to dirty
sensor/teeth, but there is definitely another problem somewhere in the
system and it's driving me nuts.

The bomb is an almost new unit from a rear ended wreck. The master cylinder
and power assist thingy are, to the best of my knowledge, original.
Hydraulic pump is two year old rebuild, hoses are all tight and dry.

Bentley is just so much greek to me on all this ABS testing with special
tools I don't have.

Any help would be appreciated - your thoughts?



Peter Berrevoets
1990 200TQ
Toronto, Canada

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