I got one of Joe's solenoid harnesses and the pump switch. I hooked everything up per Joe's video.
If I go through the process in the video, I get very little happening in the ABS brake fluid reservoir. When I pressurize the system, the fluid level drops very slightly (only about 1/16"), then when I activate any solenoid it returns to the original level. The fluid in the reservoir is very clean and never changes. I never get any dirty fluid or aerating per the video.
I hooked up the separate pump switch so I can run the pump. If I run the pump for a few seconds it slows down, so the system is pressurizing. No change in the reservoir at this point. If I select a solenoid and run the pump, the system pressurizes, then releases when I activate the solenoid. If I deactivate the solenoid the system pressurizes again (pump slows down). It does the same thing for each of the 4 solenoids. Only takes about 5 seconds of pump running for it to pressurize with the solenoids closed.
There is no change in the quality of the fluid in the reservoir no matter what I do. The fluid in the reservoir is very clean, only slightly darker than fresh fluid, and never changes. I never get any dirty fluid or aerating per the video.
Maybe there's nothing wrong with my ABS? The pump runs for about 5 seconds when I first head out, then I'll hear it run occasionally if I'm around town or at a stop. I can feel the ABS activating if i purposely activate it on a gravel or wet road. I have no record of the ABS ever being worked on, but I can't believe that it's OK with 24 years, 136K miles and no service. I looked at all the mounting bolts etc., doesn't look like anything's ever been touched. Maybe I'm just lucky?