Hi, all. Just wanted to share this with all of you in case you ever need it.

This is about the brake "octopus" (as it's sometimes called here) -- the block that has the lines from the two brake systems joining on each side of a sliding piston, to compare line pressures and warn against an imbalance.

Anyway, over the years I've had a problem twice (two different cars), with the warning light (never got a leak, though), so I thought that maybe it was a common problem in older cars. The symptom is that the dashboard warning light would start to glow, faintly and intermittantly at first, then over the weeks brighter and steadier. Since I've confirmed that it wasn't a real brake problem, I concluded, correctly in both instances, that the elements of the switch were bad (worn out) and it was grounding when it shouldn't.

What I want to share with you is that if this happens to you, you don't have to buy the whole (expensive) junction block and replace it (a lot of work), including detaching/reattaching all the brake lines (with the risk of damaging the lines), as welll as flush the system.
You can just buy a new switch rebuild kit, and unscrew and replace the little contact mechanism. It's a heck of a lot easier to replace this than the whole block.

The kit's part no. is 272702-2 (it lists for $36.23) -- this was for my 1984, but it could be for all years (at least up to '92 when they offered ABS, which could use a different system) -- and this kit contains five tiny parts:
the cap (including the electrical terminal), a gasket, a spring, an electrical contact pin, and a nylon plunger. It seems like a lot of money for so little a bunch of parts, but it's still a better alternative than leaving the wire disconnected and not having any warning.

Just so you know about this....

Regards,