Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

Dear Kaz, would it make sense to check the circuit boards for some tell-tale signs of degradation and if that is evident, then send the affected CCU, gauge cluster, SRS controller, etc. to you OR should these things be serviced at a certain age regardless?

After the boards have been serviced, how long should one wait before sending them in for the next service?

I've read in passing about dry capacitors that cannot ever leak. Repairing these boards once and not having to worry about them again sounds nice, if that would be possible.

Hi, greenberet.

It makes sense to do so but I think it all depends on one's background and taste towards servicing the car.

For the clarification, you can't judge the condition of each components based on the mileage or the age.
The main factor is the heat and how the circuit board is mounted when it comes to the leaky caps.

Based on my background and experience, I'm against the general notion of [if it's not broken, don't fix it].
If there are parts known to fail but can't be judged by the mileage or age, I'll act before they start failing for the case of NSX.
This is because it will be much more expensive, take more time to fix and very likely to damage other areas if waited too late.

On the other hand, most of the car owners prefer to spend minimum on servicing and just use up the life of the parts and wait for it to fail and then act.
Nothing wrong with this approach and again majority of the car owners follow this idea.

It's up to one's taste.


Regarding the components you mentioned, for the CCU, yes, if it was never refurbished in the past, best to inspect it and have it refurbished. Sooner is better as it will save one's cost and time.
It's mounted just above the audio head unit that can generate heat and there is not much air flow inside the CCU case.
It's mounted not horizontally but close enough for the acid to stay in one place even under vibration.
Therefore, the caps tend to leak much earlier stage than other components and it can stay at the same location for a long time making the damage deeper and much more serious than other components.


Gauge claster.
While I can inspect and replace the caps, I no longer have access to the bench system so can't calibrate the speedo and rpm as well as adjusting the volt meter, etc.
Therefore, best to send it to T3TEC in Japan.
I hope I can get hold of the used bench system in the future.


SRS controller.
Same as CCU and Gauge. It will and probably already leaking the acid from the caps on one's NSX.
I will only repair it if the owner takes full responsibility in writing for using repaired unit knowing that one should have replaced it.

On NSX Prime, someone posted that the old Legend model uses the same SRS circuit board but in different outer housing/case.
As long as it was not involved in an accident and not leaking the acid from the caps yet, it could be an option if you are doing DIY.

In fact, it will cost more to ask someone to remove and install the unit than repairing the SRS board.
The unit is held by 4 Torx bolts with red thread locking material and the mating threaded flanges are welded onto the metal bracket.
If the welding of the mating flanges are already cracked, it will spin freely once you try to loosen the Torx bolt.
You will need to apply miniature locking plier to hold the flange while trying to loosen the thread locked Torx bolts..... Happy wrenching......


For the life expectancy, as mentioned above, you can’t estimate it based on just the mileage and the age.
Also, there will be a huge difference in average temperature depending on where you live in the world or how the car is kept (inside the temperature controlled museum VS parked outside under the direct sun light around equator region).

Some of the circuit boards that I refurbished are more than 10 years old now (in Japan with four distinctive seasons) and never returned for another service (yet).

Every year, the caps technology advances so the ones I use these days won’t be the same as 10 years ago and should last even much longer.


I only joined NSXCB in Sep 2008 and started CCU service from early 2009. So far, serviced about 100 of CCU boards and none of them came back for the 2nd service.
Hope they will enjoy their CCU board with trouble free for many years to come.


Regarding other type of capacitors....

I can only offer the service that I am comfortable to do so and based on the actual test and achievement.
I know other people are using polymer caps and while it will cost more, it won’t leak the acid as they are so called solid type.
I just don't have long enough endurance test result using these type of caps on my own components especially when considering the much higher leakage current.
Probably minimum effect and fine for CCU but not sure for the Bose AMP, gauge, etc.

Kaz

Dear Kaz,

Thank you very much for the reply. My NSX is usually parked in an underground garage so it has probably seen milder temperatures than most for the majority of its life. However, it is black so perhaps it gets unusually hot when parked in the sun. It's hard to predict whether the capacitors in my NSX will have longer or shorter service lives than the average!

I bought a 2004-05 instrument cluster faceplate so when I install that, I'll check whether any of the capacitors in the gauge cluster seem to be leaking. I hope they don't start leaking before you get a hold of the used bench system.

I fully understand that you are not a believer in the old adage: if it's not broken, don't fix it. Preventative maintenance is surely a good thing if 1) the quality of parts is as good as what was installed at the factory, and 2) the quality of workmanship is as high as that in the factory.

However, I've seen so much damage caused by sloppy mechanics in various cars that I think the old adage is often right. If you, Kaz, clean and refurbish an EGR system, adjust and refurbish power windows, etc., great. If someone at an NSX-authorized Honda dealership who rarely works on NSXs and is working under time pressure does the same work, the chance of the parts being in worse shape after the service than before is depressingly high. I fully trust you to carry out preventative maintenance but unfortunately, most people don't work at the same level.