Thanks Auseeker and others,
You were right. I see a mayor leak in one of the 2 rear lines close to the rear axle, shortly before the line switches to a flex hose toward the rear brake.
It is one line to the RR brake. There are two lines, one for LR and RR that starts behind the left frame member before the tank and then disappear behind the tank and tank protection. Thank protective shield is rusty as hell and it would be a pain to remove for sure. But there is probably no other way in order to remove that old RR line.

You are absolutely right about the rust underneath and the rusted out brake line. It is a shame to see so much rust under the car that makes every move more painful than it should, down there. Every old bolt will simply be seized and snap, typically... then I need to weld (weld against what...if there is rust only) and get another thread fixed somehow for a new bolt.

At least I was lucky and I could remove the union screw (M10 x 1) from the connector fitting that translates to the flex brake hose. In the picture you see that I cut the end of the line already.

Two ways to fix this line:
1) Try and get a new line from Toyota ( Any information about the line part number number I need?). Changing that line could be a pain depending on how to get the old line out. If there are difficult line brackets to the frame (That is what I think), behind the tank, boy that could become a project.
2) Cut the end piece of the rusted out line and extend the last 2" by adding a piece of new line ( flanging etc involved... maybe also not easy down there to do the cutting and flanging).


let me know if you would do option 1 or 2.

So yes I found the leak... very happy about this. That explains the initial brake warning light that turned very fast into the full christmas tree blinking.
I understand that the hydroboost will act up if there is no fluid left for the electric pump to pressurize the accumulator... And no pressure in the accumulator meaning: the christmas tree is lit in the dash along with the christmas trompet.

Is it true that the accumulator pressure will activate the dash lights? If the pressure is too low the dash starts acting up?

Well before I drove the car into the garage yesterday I filled the brake fluid reservoir , started the engine but I did not hear the booster motor runnning as it should.
There could have been simply no pressure building up with the leak and therefore the motor does no sound?
Or it did run and I did not notice because it was running with no load on the pump... fairly silent?
What Pump is Toyota using for the booster? Is this a simple gear pump?

I am trying to go step by step.
First to get the leak fixed and then test if the booster motor works (maybe do some bleeding first in order to remove a good portion of the air?)

Thanks, Martin

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