how much is the working pressure (bar) of the ABS system ?

[stankosab]

I'm checking the ABS system and need some information:

how much is the pressure (bar) of the ABS system when at working regime?
at how many bar the pressure switch turns off the ABS pump ?

[Kaz-kzukNA1]

Hi, stankosab.

I have never measured it by myself as I never required it for any ABS diagnosis.
One of the NSX Prime member carried out some testing and probably these are what you are looking for;

http://nsxprime.com/forum/showpost.php?p=983606&postcount=35


Based on your previous post regarding your ABS issue and your OP, I presume you are still having some issues with your ABS??


If that is the case, then I don’t think you will need to measure ABS pressure.

You can carry out the basic checks using the Workshop Manual.

For example, you can read the error code to start with, you can check the ABS pump relay by applying 12V, you can manually override the ABS pump by shorting the 2 terminals at the relay socket, you can check the pressure switch with the multi meter while operating the ABS pump, etc, etc, etc…
All of these are in the manual.

The accumulator is bladder type with high pressure nitrogen gas inside.
Therefore, if there is enough nitrogen gas left, you can pressurize it to really high level but it is more important to measure the amount of fluid stored inside the accumulator than measuring the actual pressure.

While overriding the ABS pump, you can also check for the leaky solenoids and if you apply 12V on each solenoids, you can confirm the stuck closed or leaky ones as well.

Hope you will recover your ABS…

Kaz

[stankosab]

Kaz

thanks for the advice

the pump starts regularly (making noise) after the engine start, it runs for 2 min than it stop and the ALB light comes ON on the dashboard.
I brought the car to the Honda dealer to check whats wrong, they applied the ALB tester and was told me that the circuit do not reach the working pressure probably due to fail of the pump group or the accumulator , don't know what allarm code come from ALB tester.
now the car is in my friend's workshop, i forwarded to him the instruction of how to bleed the pomp group and how to eccitate the solenoids.
but before he tried to bleed the pomp group by the bleeder as a normal brake circuit, and he say that running the pump and opening the bleeder , there isn't any oil spilling from the bleeder, as if the pump run dry.
he have checked the inlet hose from the reservoir and says that it is free from obstructions.
is normal that there is not oil coming out from the bleeder with the pump running? i suppose that the bleeder should be under pressure because is positioned at the outlet of the pomp, connected to what looks like a small filter before of the hose thread
does it worth to disassemble the pump to check if something is stuck inside?

considers that, in the last three years, the car was stopped in a garage without being used

Davide

[Kaz-kzukNA1]

Hi, Davide. Thank you for the extra information. It always helps by providing the detailed info in supporting anyone with their issues.
It would be best if we combine this thread with your original ABS issue one as it is starting to get off the topic against your opening post but let’s see how it goes.


Based on your latest information, you were at least getting ABS error code #1.
ABS controller is monitoring the status of the pressure switch and if it can’t achieve the threshold pressure once the pump has been activated for 2min, it will trigger the error code #1.

From what you wrote, it seemed that your ABS pump was at least operating.
Therefore, the system couldn’t achieve the threshold pressure because of the following reasons;

1. There was an air pocket in the low pressure rubber hose connected to the ABS pump and thus, it simply couldn’t push any fluid into the accumulator.
2. The accumulator lost so much nitrogen gas that there was not enough back pressure and the pump simply couldn’t pressurise the system.
3. One or multiple solenoids were stuck open and leaking the fluid that any pressurised fluid at the accumulator was simply leaked out to the reservoir.

For the case of no.1, you can tell whether the pump is pushing out any fluid or not by simply monitoring the fluid level at the reservoir. As soon as the pump is activated, the fluid level will go down. If not, your pump is not getting any fluid.

For the case of no.2, you need to monitor the amount of fluid recovered to the ABS T-wrench.
Seems like you didn’t get any fluid into the T-wrench so either you have big hole in the diaphragm of the accumulator or very likely to be the case of no.1.

For the case of no.3, you can monitor the state of the return port inside the reservoir. While you are activating the ABS pump, you should see no fluid or bubble coming out of the nozzle protrude from the meshed filter. The fluid level should go down while no fluid/bubble from the return port. If you see anything, one or some of the solenoids is/are leaking.

Should be enough at this stage.

Kaz

[stankosab]

Kaz

I have solved my ABS issue, upgrading all the Pump Group with a 2nd generation NA1 , bought from a member of the forum.
now the ABS work properly.
anyhow, the the problem with the old group seems to be the pump itself , not able to build any pressure,not even able to push oil out from the bleeder.

thanks for all your advices, I'm building some knowledge reading your threads.