Tci repair

I opened up my Tci module this past weekend, to replace the caps and the transistors. BTW these modules were not designed to be opened. You can't just turn the screws to open it, all you will do is strip the screw heads.
Most of the parts inside are obsolete no big surprise there.
Luckily the ceramic substrate wasn't broken or cracked. The substrates are very hard to repair, I wouldn't even think about touching it.
A solder iron will crack it quick.



I'll plug it back into the 550 this weekend, it should work better than new.

 

I had to open my 550's TCI and rework all the corroded PCB traces. The most annoying thing is that the copper layer separated from the PCB with minimal heat from the soldering gun... so I had to fix more than just the obvious. In the end though, it worked like a charm. Good luck with yours!

 

So exactly how do you open one up?

 

If it's anything like mine, four screws to open the back cover, then desolder the plug from the circuit board.

Stereo: how much wattage did you have going? I think I used a 15/30-watt Radio Shaft special for mine, and had no problems.

 

If by traces you mean the conductive paths,they're may be an alternate repair. I used to service photocopiers,and when I couldn't get a replacement PCB,I would repair the original one with the stuff used to repair automotive rear window defroster grids. Merely paint it on,and conductivity is restored.No concerns about heat buildup,either.

 

To open it up, I used a small micro torch to heat up the screws. There is some kind of clear goop on the screws and they won't loosen unless they are hot, but be careful to not melt the plactic housing.
The other 2 problems I ran into is the conformal coating on the pcb and the hard goo they smeared on the electrolytic caps. I imagine that was for vibration protection, it looks like it worked well because it was a pain to get it off the parts.
To repair the traces if they lift off the pcb just super glue them back down.
If the conductor is broken I would normally use a piece of buss wire or solder a piece of wire across the broken trace.
Before I close the module I'm going to put some rtv around the caps and the connectors to make it a little more water resistant.

 

heh, I used the same exact iron - 15/30w from Radio Crack (we all got a name for it, don't we?). Now that I think about it, I shoulda borrowed an SMD rework station from our office.

I think part of my problem was the fact that after sitting in a barn for 20 years, some moisture found its way into the TCI, and basically ate the traces right under the coating. I ended up using wire to repair most of them, because they turned all green and brittle.

One of the screws came out without fighting, but the other one was corroded pretty bad (that's where the moisture got in). I dremelled it off and replaced it.

 

Right. Mine came off fairly easily. The article I was using as a reference (I've mentioned it many times before; search the forums for Dave Jack) says that it's nothing more than standard contact cement. So, having a gallon can of the stuff at the center where I work, after I replaced the caps I drizzled some over the new ones.

As for the "conformal coating", if you're referring to the sealant on the back side of the board, that can be gotten off fairly easily with a spare toothbrush and acetone. My big problem with that was finding a can of the sealant to put back on afterward.

Rat Shack it is. At least, I *think* that was the one I used. I've also got an old Weller solder station here with the variable temperature control. Used that one to solder up the wiring harness when I upgraded my car stereo.

 

Clear Polyurethane or Acrylic spray will work for a conformal/sealant.

 

<nod> The stuff I got says it's "A high solids acrylic resin designed to protect and encapsulate dry transfers applied to wood and non-porous surfaces." DataKoat is the name of the stuff.

 

couldnt you use the red 'battery teminal protector' spray? im not sure how conductive it is, but i know it is supposed to form a water / air tight barrier

 

No idea, I'm afraid. This Datakoat stuff is what the author of the article suggested, so that's what I went with.

 

I would avoid the battery terminal spray, while it is non-conductive it would be a royal mess and eventually drain off of the surfaces (might take 6 months to do it but it would eventually slide off). My two cents.

 

don't use RTV to hold caps or seal circuit boards
rtv adhesive
i bedded the barrel of a .22 with it and a year later had pits 1/8 inch deep

 

Hi all.
I have recently changed my entire loom (see 'another new user' in the General lounge) the replacement came with a TDI attached. My Question is, should I put the old one back in or leave it alone? The original is a type TID14-21 29R-10 and the new one is Type TID14-37 58L-10. Does any one know if it makes any difference? This bike has not run for about 2 Years.

 

This is not uncommon. When most RTV's cure, they outgas ammonia, a corrosive. Best to use urethane, especially when in contact with metal. Sorry to hear of your undoubtedly undesirable experience.