How to fix the ICU for less than $5

Just let me begin with a little bit of history: back in early 90’s honda used some bad capcitators in their electronics. Over the time they will leak and cause the capacitator to short itself and also do some damage to the boards. The items affceted are the 90-93 ICU’s 90-93 Accord TCU’s and some more.

anyway i won’t get into details on how to remove the ICU. I will let you figure that out because i used lots of brawn and not enough brains there, but there is another story.

Tools needed:
Soldering gun/iron
Solder
Small Screwdiver
Small Wire Brush.
Magnifying glass.

Parts needed:
100microfard cap, 16v 105C degrees ( i used a 200microfarad 35v 105c cap)
Small Wire (i used one of the wires from the cd-rom to the sound card lol)

once you get the ICU out pry it open and look at it. The circuit boards will show black in some cases under the 100 microfarad cap. Unsolder the cap (keep in mind which way the white line is because it is polarity dependent) from the backside, and clean the board as good as you can, in the begining with some alcohol (i used my aftershave, but that’s another story), then i used some radioshack brush. After the cleaning is done use the magnifying glass to look at the damage to the board ( the insulator stuff in the cap is higly corosive and will damage the board). If it is way too bad i sugest you replace it completely. After you fix the board put in the new cap with the exact polarity. Put the board back in it’s box and assemble the car. Everything should work just fine now.

This is what works now:
intermitent wipers
i can hear the sound when the turn signal is on
the rear defroster works just fine (no refusal to turn on, or beingon all the time)
side marker lights are not coming on with the engine, but they come on with the car,
the brake light comes on when the brake fluid is low.

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were is the ICU located at because I also have to fix mine too.

it is behind the fuse panel under the dash. if you take out the fuse panel the icu is clamped behind it.

Wow so it’s just a bad capacitor? How’d you find that out?

thats a great bit of info — WTF is a microfarad?.. golly gee…

Unit of capacitance :stuck_out_tongue:

It is people like ebpda9 that make me proud to be a g2ic member and car owner.
Thanks for posting this.

nice tip!

I just recently lost my intermittent wiper setting, instead it goes fast now. This ICU is the culprit right?

i cant believe more people arent jumping over this… it actaully works! the only thing is that the paths might be destroyed but if anything go to a junkyard and start ripping icu’s from integras and check em out.

done done and done =) thanks for the tip :up:

-kenny

So whats the difference in getting a 100microfard cap, 16v 105C degrees and getting the one that you got that was 200 microfarad, and 35v?

I have a catalog from www.digikey.com, and there are quite a few capacitors in there. Just cost between $.30-80 cents. But there are many different models. They are all Phillips, and have the same specs as above.

I just emailed my lab professor about this cap thing. I’ll let you know what he says. This guy really knows his stuff!! I’m weary about changing the specs on the cap.

It looks like a higher rated voltage will solve the leaking problem. He wants to see the cap, so I will be bringing it to him tomorrow and let you guys know for sure. Also need to find out how to clean up the gunk on the circuit board.

I just picked up an icu out of a teg my friend stripped and is junking. Luckily it’s perfectly clean inside. No leakage. I’m gonna replace the capacitor anyways. Neil, have you looked into changing the other one out as well, the one to the left that is 105c, 33 microfarad & 35v. Since they used crappy capacitors for them, it might be worth it to just swap both.

I just couldn’t figure out what would change going from 100 to 200 microfarad. And what would change going from 16v to 35v.

I’m gonna fix this one, and order up extra capacitors to fix mine when I swap it out with this one, as well as repair a few friends units as well.

Well I ordered a 10 pack of 493-1856-ND, and a 10 pack of 493-1779-ND. from www.digikey.com They are the same brand Nichicon. But not the same model. I ordered both capacitors just in case I decided to change out both of them on the board.

The Panasonic’s are a little cheaper by the 10 pack, P11198-ND and P10290-ND

Also got a desoldering pump vacuum for $20 to suck the old solder off the board.

I just had the talk with the professor. It turns out that the most likely reason the capacitor is failing is the VOLTAGE rating.

So get the higher voltage rating of 35V. The temperature is irrelevant. The capacitance should not be reduced, but you can go higher. Chances are that the engineers got the capacitance correct, but not the voltage.

I don’t know about replacing the other one. I didn’t know the other one was 35V. Since that one didn’t fail, that seems to better support the hypothesis that the 16V just isn’t enough.

Keep the capacitance the same… higher capacitance equals more cost anyway.

I’m working on getting a “ICU repair/exchange” program going for the G2ICers. So look for that soon.

And as for removing the electrolyte that has spilled and backed onto the surface… try a Qtip with water. Dunno if that would do anything though.

ok I ordered a 10 pack of these as well 493-1861-ND (Nichicom 100mf, 35v, 105c)

So this is why intermittent setting on my wipers doesnt work most of the time? What about my rear defrost comming on by itself and not turning off, that too?
No key in with the door open chime as well?

would the defrost doing its own thing cause my fogs no to turn on anymore…?

I dont think so, but I thought that Id ask…

TIA!

are your fogs wired to your defroster so they can turn on independent of your headlights?

Dwayne my defroster would come on by itself all the time. Now it’s totally dead. My intermittent wipers never worked. I think it goes away one at a time.