Replacement parts list inside TCI

Here is the parts list I used to re-build my TCI:

Capacitor 47uf 50v Electrolytic Radial
Digikey 493-1106-ND

Capacitor 10uf 25v Electrolytic Radial
Digikey 493-1057-ND

Capacitor 2.2uf 50v Electrolytic Radial
Digikey 493-1100-ND

Transistor Darlington MJE5742 (replacement for ETD41-035)
Digikey MJE5742GOS-ND

Capacitor 4700pf 50v Ceramic (replaces green radial mylar caps)
Digikey P4944-ND

The 3 different Zener diodes are obsolete. They can be purchased, but every place I tried had a $100-$250 min. purchase.
I don't need that many diodes. :lol:

The first one is a Hitachi 1SS108 this one has a white stripe on one end and a letter "H" surrounded by a black strip.

Hitachi 1S2075 has a Green band on one end and a letter "H"

Hitachi 1S2074 has a green band on one end and a letter "H" surrounded by a white band.

I used acetone to clean the goo (conformal coating) off the circuit board.
Once I soldered the new Electrolytic caps on the board I ran a bead of hot glue along side of them, this will prevent vibration from breaking the leads.

I didn't mess with the ceramic substrate. Heat from a solder iron will cause them to crack. The only way to replace parts on them is to use an oven to heat the whole substrate up at once. If its cracked it's junk.

On the TCI if you don't know how to solder, don't even attempt to repair it.
Find someone who knows how.
This list was used to repair the TCI on my 81 XJ550.

On other bikes the parts will be very similar if not exactly the same.

The only way I was able to open the TCI module is by using a torch on the heat sink located on the bottom. But you need to be careful to not melt the plastic surrounding it.
It only needs to be lightly heated to get the screws loose.

Don't barbeque it or it will be junk. 8O

Once I was done I coated the circuit board with conformal coating and resealed it back up.

Don't use solder with water soluble flux.
Only use rosin core solder or no-clean and don't worry about cleaning the flux off.

I think thats it.

Art

 

I thought of something else....

The electrolytic capacitors are polarized that means one leg is + and the other is -
Remember how you take out the old cap.
The new cap gets installed the same way.

 

Just curious but why did you need to replace so many parts?

 

Electronic parts degrade over time, after all they are 27 years old.
As they age the tolerances get wider until they fail. Sometimes when one part fails it also takes out another part or more.

The reason I replaced so many was just a preventative measure. I replaced the problem parts.

Some of the components Yamaha used in these modules are cheap....really cheap. Brand names I never heard of.