Sticking ABS Brake Solenoid Fixed

[Jadams1]

Symptoms: ABS pump running for extended time after hitting the 8 mph triggered ABS pulse and occasionally while driving.

I flushed my ABS system last night using Danolands writeup and the YouTube video. I started out by sucking out the old brake fluid in the reservoir and filling with new fluid. Ran the pump for 30 seconds and I could see return flow into the reservoir so one or more of my solenoids must have not been 100% seated. I cycled through the solenoids, each one got 5 short bursts. I sucked out returned fluid from the reservoir and refilled, then ran the pump. No return flow was observed when I re-primed the accumulator this time. I repeated the whole process 4 more times until the fluid in the reservoir looked new. Drove the car and all is good.

I didn’t have the symptoms all the time, the symptoms were more pronounced on the first drive after the car was stored for winter of if not driven enough.

Note: I did not drain the accumulator from the service valve.

Danoland’s Writeup http://www.danoland.com/nsxgarage/brakes/abs/abs.htm
ABS Solenoid Exercise Video https://www.youtube.com/watch?v=j0w9pKs00QE

Thank you Danoland for your great writeup. Here’s a pic of my test rig setup.

 

[8R6]

thats all you need to do to flush out the brake fluid?! My ABS has been acting up exactly like you described and just recently last week, it overflowed out of the reservoir cap too.

I always thought to fully bleed and flush a brake system, it gets drained/vacuumed from the brake lines?

that's an awesome video

 

[Jadams1]

The brake fluid circuit does not come in contact with the ABS loop, they are separate loops. Could be you have a stuck solenoid like I did which would explain the foam in the reservoir. I built the test harness with stuff I had laying around and used $8 worth of brake fluid. There is a t-handle tool that allows you to purge/empty the ABS accumulator that I do not have. The method I used just dilutes the old fluid with new fluid, I used 32 oz of new brake fluid to complete the service.

The write up that danoland did and the video was a huge help.

 

[8R6]

The brake fluid circuit does not come in contact with the ABS loop, they are separate loops. Could be you have a stuck solenoid like I did which would explain the foam in the reservoir. I built the test harness with stuff I had laying around and used $8 worth of brake fluid. There is a t-handle tool that allows you to purge/empty the ABS accumulator that I do not have. The method I used just dilutes the old fluid with new fluid, I used 32 oz of new brake fluid to complete the service.

The write up that danoland did and the video was a huge help.

ahhh ok i didnt know that. good to know! thanks man

 

[KraftwerkTurbo]

When taking out the manual NSX last time for some AC work, the ABS and TCS lights came on after sitting in the cold a bit.
Sucked out all fluid from all 3 (what is the really small one for) and filled with ATE fluid.
Since my pressure bleeder is not working with the NSX reservoirs, I did a 2 man flush (open, push, close, retract), about 1.5 quarts.
Topped off all 3 reservoirs.

As soon as driving forward for 50 years, both lights came back on.

With lights on, cannot activate ABS, so only way is using the 'manual' method.

Since ABS and TCS light are on steady, does that mean that ABS solenoids are 'stuck'.

From the write up

http://www.danoland.com/nsxgarage/brakes/abs/abs.htm

should I start with the 2nd part "Solenoid Flush"?
I don't have "Bleeder T Wrench" (and haven't seen photos, so don't know if a work around or ghetto tool is possible), so if it is essential and if I also need to do the first part "flushing the ABS", then I probably need to look into buying one?

 

[KraftwerkTurbo]

Best way to go about getting the harness (to activate the solenoids), pump switch (no messing with wires/shorts) and the Bleeder T Socket?

 

[Lude_2_NSX]

I also just recently did this after rebuilding the whole modulator (new o-ring kit). Haven't heard the ABS pump in almost two weeks! It used to come on almost every time I drove it in the morning.

 

[KraftwerkTurbo]

How (what did you use, tools, harness, etc?) did you do it? Both pump flush and solenoid flush?

 

[Lude_2_NSX]

How (what did you use, tools, harness, etc?) did you do it? Both pump flush and solenoid flush?

I bought an oring replacement kit, rebuilt the modulator assembly and then performed the bleed.

You need a the honda bleeder tool, or I used a 3/8" drive head and channel locks with a regular bleed tube. Be very cautious working on this as this is under very high pressure.

I built a test harness much like the OP has, and performed the bleed procedure that has been outlined many times in this forum to run the pump, actuate solenoids, refill reservoir, and repeat...