ABS fluid leak onto garage floor

[nikey22]

1994 NSX

Noticed that car would run the ABS pump during every drive ~once a week driven car.
It would run for about 10-15sec, then all is well.
ABS not used much routinely.

Parked car in garage, noticed an ABS fluid puddle on garage floor after a few days. Fluid is above max in the ABS reservoir. Fluid is normal in the brake reservoir.
No brake light (CEL).

My question is, when the ABS pump fills the accumulator with brake fluid, and if it is not used (car is parked), where does the fluid go, and why did it leak out of the reservoir?

 

[asylum]

Leaking pump, accumulator or high pressure line... This will lead to spilage on the floor

What do you mean by "above max" in the ABS reservoir ? Is it overflowing causing the puddle ? This could be the case if one of the 4 solenoids is not tight (-> fluid goes back from accumulator to reservoir). But I do not think this is the case because a leaking solenoid would lead to a lot of pressure loss in the accumulator and a pump that runs really often.

 

[anesthesia]

Most likely you got a stuck seloinds and your abs system can not pressurized. Go “exercise” the abs by finding dirt/ open road and slap on brake to see if you can get seloinds unstuck. Jm2c

 

[nikey22]

Thank you for the responses.

Asylum:
The high pressure hose, the accumulator and the pump all seem intact and dry. I can only assume that the puddle was caused by overflow from the ABS reservoir as the plastic warning label was also "wet" with fluid. So to test your theory about "tightness", here is what I did: I filled the reservoir with fluid to max, removed ABS relay and energized the ABS pump for about 30sec, and observed for a few minutes. There was a predictable decrease in level of the fluid and NO small, foamy bubbles creeping into the reservoir fluid. This tells me all the inlet valves are closed and ONLY open when I energize the RED-BLACK circuit.

anesthesia:
I did this for 1wk straight. No Leaks. So, so far so good.

Kaz (UK):
Thank you for your explanation and insight on the UK site.
I'm curious when we use the Dan-o-land procedure for exercises the solenoids, we are only energizing the RED-BLACK circuit which is the inlet valve (lower valve) of each solenoid.
In actuality, for each solenoid there are 2 wire loops. One for the inlet valve (RED/BLACK) and the other for the outlet valve (YELLOW/BLACK). The outlet valve is exposed to atmospheric pressure via the reservoir and is always open. That's why we are able to see the millions of fine bubbles when we open the inlet valve. The fluid just rushes upwards.
If you were to energize both circuits at the same time (which the car does), you should be able to feel a tiny kickback pulse on the brake pedal (if someone else was in the car), since the only place the high pressure fluid could now go would be into the piston assembly of the modulator and then into the brake line and onto the brake pedal. It would be about 1/4 strength because you're simulating a lock in only 1 of the 4 channels.