kermac
08-20-2010, 01:51 AM
I've checked out all the posts on brake fluid leaks (it causes your handbrake light to light up and beep at you when the level gets too low). Most of the stories are about low fluid caused by pad wear or leaks around the pistons/calipers.
My leak is at the ABS control unit. There's a little puddle of the stuff sitting on the bracket that supports the ABS unit. I have to top up the fluid every couple of hundred miles.
Anyone know what's the story with the ABS control unit? Where is it likely to leak from? Are there rubber seals in there? My Bentley manual doesn't tell you much about pulling it apart to check for bad seals.
Here's a clue to the possible cause: a couple of months ago I was doing a routine top-up (oil, coolant, power steering fluid etc etc) and I had just tipped a few cc's of power steering fluid into the brake reservoir when I realised it was the wrong colour (similar shaped bottle!) I immediately stopped pouring and siphoned out the whole reservoir. Shortly afterwards I had the entire brake system flushed out and refilled.
At the time this happened, the level had not sunk very much, so it seems there was no leak before I mixed the fluids. My guess is that the remaining PS fluid in the system (can't have been much) mixed with the brake fluid and caused the seals to melt.
So the nub of the matter is that I seem to have a leaking ABS unit and how do I fix it short of morgaging my house and getting the dealer to do it for me? He will doubtless want to replace the ABS unit, reservoir, all four brake calipers, hoses, etc etc.
Anyone got any ideas?
Thanks
(copied to A4 forum)
My leak is at the ABS control unit. There's a little puddle of the stuff sitting on the bracket that supports the ABS unit. I have to top up the fluid every couple of hundred miles.
Anyone know what's the story with the ABS control unit? Where is it likely to leak from? Are there rubber seals in there? My Bentley manual doesn't tell you much about pulling it apart to check for bad seals.
Here's a clue to the possible cause: a couple of months ago I was doing a routine top-up (oil, coolant, power steering fluid etc etc) and I had just tipped a few cc's of power steering fluid into the brake reservoir when I realised it was the wrong colour (similar shaped bottle!) I immediately stopped pouring and siphoned out the whole reservoir. Shortly afterwards I had the entire brake system flushed out and refilled.
At the time this happened, the level had not sunk very much, so it seems there was no leak before I mixed the fluids. My guess is that the remaining PS fluid in the system (can't have been much) mixed with the brake fluid and caused the seals to melt.
So the nub of the matter is that I seem to have a leaking ABS unit and how do I fix it short of morgaging my house and getting the dealer to do it for me? He will doubtless want to replace the ABS unit, reservoir, all four brake calipers, hoses, etc etc.
Anyone got any ideas?
Thanks
(copied to A4 forum)