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Bad tci diode? Please take a look
- Thread starter Jaydela180
- Start date
9226356
XS650 Enthusiast
Great camera! I can't see anything obviously wrong. It was my understanding that if a component failed the whole board would stop working.
That is just glue they put on some of the components to keep them from being subjected to so much vibration. ZD would mean it's a Zener diode which is like a little voltage regulator for some part of the circuit.
First time I've seen that final drive transistor D991.
Normally see a etd41-035 in there.
More info: http://www.eevblog.com/forum/projects/looking-for-transistor-data-etd41-035/
The 2SD991 is a Hitachi part.
on eBay: http://www.ebay.com/itm/400667323729
Spec sheet:
Normally see a etd41-035 in there.
More info: http://www.eevblog.com/forum/projects/looking-for-transistor-data-etd41-035/
The 2SD991 is a Hitachi part.
on eBay: http://www.ebay.com/itm/400667323729
Spec sheet:
Jaydela180
XS650 Addict
Jaydela180
XS650 Addict
Ill report back about hesitation when float level is correct.
I originally intended to replace every component on my TCI but unfortunately it had an IC that was no longer available. The IC was a quad op amp package but with additional custom circuitry (I think it had 18 pins). On later TCIs they changed to a different quad package which has a direct modern replacement (14 pin LM2902N). My SH TCI did not have a true advance system i.e. on revving the engine the advance would jump from the idle setting to the fully advance setting with no in between positions (Perhaps it was broken). Knowing I could not do a complete component replacement I opted to change to a modern system with a true advance system which mimics the older points systems. I used the Boyer Bransden ignition.
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Note: If you have the TCI with the 14 pin HA17902P this can be rebuilt using the LM2902N and every other component can also be replaced. But I think it is better to just go for a modern replacement ignition.
Replacing every component is not the way to do it! The electrolytics are the least stable but also the least critical. Mylars and semiconductors still not critical and don't really age. IC package, does not age at all except by cumulative damage. One thing you can do is reflow every solder joint if you are good at soldering. The joints are prone to failue and you can see a little ring around the leads sometimes with a high-powered magnifier (like a loupe).
Replacing all the components can be the way to go, but it is not the only option available. The choices we make when doing repairs depend on what we consider to be the best practice for maximum reliability and peace of mind.
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^I think I read somewhere that some of the components are selected for value, so replacing those might mess it up. I seem to remember you can see where those have been soldered in by hand after the rest of the board went through the solder. Probably time constants controlling the advance or something.
Bob Kelly III
Ranch Kid from way back,.... that got Old !
in my Electronic years ( ham radio stuff) I replaced many components with off the shelf "Close enough" stats.... and they all worked fine
it's amazing what you can get away with in electronics ! I replaced critical components like final amplifier OP amps with larger ones
that should not have worked according to other ham nuts at the time... and it worked just fine with no drifting in frequency ....
My dealings with Motorcycle selenium rectifiers however, was not as successful you would think just replacing them with the proper diodes would do the trick but it didn't happen ! I have no idea what I did wrong ! but it didn't work ! I had to steal a rectifier off a junk bike to make it work again...
.... Alot of automotive electronic components are Very Robust as compared to normal electronics that run on 12 volts, you would think if it's 12vdc its good to use but that's not always the case in many automotive components they have a higher tolerance to High voltage spikes which is what usually takes out the components in the first place.... so when Looking at replacement parts Look at it's ability to withstand transient voltage spikes without damage.... although that is not always possible as most of the time you are given such cryptic information on what the component can do and tolerate that you are left with wondering what their meaning for,Ns, vtn or dsw , or any of the letters that they have in their charts mean !!!!!
Over the years I learned to look for those letters and numbers and although many sites change the letters and numbers to their components
they will have a conversion chart ....most of the time.... if they don't don't buy from them because you have no idea what your getting !
.....but Buying a component that has Higher than the stock component is what I like to do and I've never had that fail.... although things like input voltage 0 to 15vdc must stay the same and not 0 to 5vdc,... going to 0 to 25vdc is ok . and is less likely to burn out over time.
.....
I remember replacing the diodes in an alternator one time by buying the proper diodes at a napa auto parts store... it cost like $5.00 or so ...
I soldered them in there and put the beast back into service and the next month the bearings started going out ! I would have been much better off replacing the bearings at the same time I did the diodes ! .... one of those DUH ! moments ! lol.....
....
Sense the TCI unit is electronic in nature about the only thing that can go wrong with it is being bombarded by high voltage spikes
so make sure all your grounds are clean and not rusty ..... over voltage would have to be very high to damage the TCI unit if what I know is correct
it's built like a tank ! so the only thing you have to worry about is the power, ground and vibration.... the TCI units should outlast the bike and then some..... swapping out a TCI unit's Computer (as some call it) from an old used one should be fine and have a real good chance of working just fine.
just thought I'ed mention that !
replacing components is not rocket science.... even I have done it , and if I can do it anyone can ! LOL
using either Solder Wik, to slirp up the old solder of a vacuum bulb. leaves less excess solder on the board and less chance for a bridged gap somewhere else.... a low wattage soldering iron and an eye for heat.... heat is the enemy of electronics .... make your components secure
in the board by bending the leads on the underside of the board then clip them off.... don't expect the solder to hold them
don't use high temp solder for plumbing ! use electronic solder.....and you'll be fine.
.......
f.w.i.w.
Bob......
it's amazing what you can get away with in electronics ! I replaced critical components like final amplifier OP amps with larger ones
that should not have worked according to other ham nuts at the time... and it worked just fine with no drifting in frequency ....
My dealings with Motorcycle selenium rectifiers however, was not as successful you would think just replacing them with the proper diodes would do the trick but it didn't happen ! I have no idea what I did wrong ! but it didn't work ! I had to steal a rectifier off a junk bike to make it work again...
.... Alot of automotive electronic components are Very Robust as compared to normal electronics that run on 12 volts, you would think if it's 12vdc its good to use but that's not always the case in many automotive components they have a higher tolerance to High voltage spikes which is what usually takes out the components in the first place.... so when Looking at replacement parts Look at it's ability to withstand transient voltage spikes without damage.... although that is not always possible as most of the time you are given such cryptic information on what the component can do and tolerate that you are left with wondering what their meaning for,Ns, vtn or dsw , or any of the letters that they have in their charts mean !!!!!
Over the years I learned to look for those letters and numbers and although many sites change the letters and numbers to their components
they will have a conversion chart ....most of the time.... if they don't don't buy from them because you have no idea what your getting !
.....but Buying a component that has Higher than the stock component is what I like to do and I've never had that fail.... although things like input voltage 0 to 15vdc must stay the same and not 0 to 5vdc,... going to 0 to 25vdc is ok . and is less likely to burn out over time.
.....
I remember replacing the diodes in an alternator one time by buying the proper diodes at a napa auto parts store... it cost like $5.00 or so ...
I soldered them in there and put the beast back into service and the next month the bearings started going out ! I would have been much better off replacing the bearings at the same time I did the diodes ! .... one of those DUH ! moments ! lol.....
....
Sense the TCI unit is electronic in nature about the only thing that can go wrong with it is being bombarded by high voltage spikes
so make sure all your grounds are clean and not rusty ..... over voltage would have to be very high to damage the TCI unit if what I know is correct
it's built like a tank ! so the only thing you have to worry about is the power, ground and vibration.... the TCI units should outlast the bike and then some..... swapping out a TCI unit's Computer (as some call it) from an old used one should be fine and have a real good chance of working just fine.
just thought I'ed mention that !
replacing components is not rocket science.... even I have done it , and if I can do it anyone can ! LOL
using either Solder Wik, to slirp up the old solder of a vacuum bulb. leaves less excess solder on the board and less chance for a bridged gap somewhere else.... a low wattage soldering iron and an eye for heat.... heat is the enemy of electronics .... make your components secure
in the board by bending the leads on the underside of the board then clip them off.... don't expect the solder to hold them
don't use high temp solder for plumbing ! use electronic solder.....and you'll be fine.
.......
f.w.i.w.
Bob......
I had one fail and I worked with it forever until I discovered that the solder joints failing is a common problem, possibly the most common. If you look at them with a strong magnifier and sharp eyes you can see a little ring around some of the leads sort of like a plug of solder connected to the lead wants to break away from the rest of the solder. What happens is the joint is intermittent even though it looks like it should still be making contact. A typical symptom is the bike will just shut down out of the blue, but will easily start up again. It misses a pulse or something which shuts it down. To fix it just skillfully reflow every joint. Also, there are four big white and yellow diodes that I think are prone to breaking because I found an identical one broken inside a relay. I replaced them with 1N00X series diodes.
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Also, the solder joint looses its uniform shiny appearance and a dull band starts to appear around the soldered component lead prior to the crack forming. In Entry 1 above I believe this is what has appeared on several joints in the photos e.g. see the l leads of the Darlington transistor and the bottom Zener next to the silicon diode. With theses TCI boards the main cause must be the vibration rather than heat so I would also put some hot melt or electronic sealant next to the large components e.g. the resistor at the bottom by the silicon diodes. Care must be taken when resoldering the zener diodes. They have a tendency to crack if over heated. I usually hold their lead with long-nose pliers during soldering to act as a heat shunt. Those wires to the 8 pin connector may need to be reheated also.
For reflowing solder joints I always use the lead based solder which the TCI will have been made with. I apply some flux, the brand I use is the Fluxite as it does not cause corrosion long-term. In my damp garage I have a metal detector circuit board that I build in 1984 and the board is still in near perfect condition even though all the Fluxite was not clean off.
HP had a series of laptops a few years ago (Pavilion Series) where the graphics chip would heat up and eventually cause a phase change in the solder and the connections would fail. The cure was to remove the chip using an IR heater, clean the connectors and reball with the older lead based solder - fiddly job to do. The lead based solder is better long-term in the presence of heat. With vibration maybe the silver solder is mechanically better, but I just do not know this aspect of lead verses silver??
When I examined my TCI there were at least 20 bad or suspect joints so I reflowed everyone. In the Entry 1 above the joints on D4, D10, R43 and the Darlington and several others look suspect to me, but it may just be the lighting conditions.
May be worth checking all the ignition wires where they meet a connector because they may have broken behind the insulation. Just pull the wire a little, if it stretches a bit then there is a break.
Good luck but as suggested by others above look for the obvious first.
For reflowing solder joints I always use the lead based solder which the TCI will have been made with. I apply some flux, the brand I use is the Fluxite as it does not cause corrosion long-term. In my damp garage I have a metal detector circuit board that I build in 1984 and the board is still in near perfect condition even though all the Fluxite was not clean off.
HP had a series of laptops a few years ago (Pavilion Series) where the graphics chip would heat up and eventually cause a phase change in the solder and the connections would fail. The cure was to remove the chip using an IR heater, clean the connectors and reball with the older lead based solder - fiddly job to do. The lead based solder is better long-term in the presence of heat. With vibration maybe the silver solder is mechanically better, but I just do not know this aspect of lead verses silver??
When I examined my TCI there were at least 20 bad or suspect joints so I reflowed everyone. In the Entry 1 above the joints on D4, D10, R43 and the Darlington and several others look suspect to me, but it may just be the lighting conditions.
May be worth checking all the ignition wires where they meet a connector because they may have broken behind the insulation. Just pull the wire a little, if it stretches a bit then there is a break.
Good luck but as suggested by others above look for the obvious first.
Bob Kelly III
Ranch Kid from way back,.... that got Old !
Good info there guys ! and here I figured the TCI units would never ever fail ! good to know what to look for ! thanks !!!!!
......
Bob.........
......
Bob.........
I've done two. I used very thin rosin core solder, just a tiny dab to each joint, with no separate flux. Then I cleaned off all the rosin with denatured alcohol and a toothbrush. I rode that all over the country in all kinds of weather without a problem. Finally I had some clear spray lacquer so I gave the solder side a few coats of that; figured it couldn't hurt
I used to be a programmer in an electronics lab and the techs had some kind of water-thin flux in little bottles with a needle. I wish I remembered what that flux was. Their standard procedure to replace smt chips (with ones containing new code) was to heat the chip with a little torch until it would flip off using a dental tool, then put the flux on the pads and set the new chip on them and heat the new chip with the little torch. No additional solder needed. When the solder melted you could see the chip sink about 0.1mm and it was ready to go. You can get solder these days that is really no good, environmental something. I'm glad I have a lifetime supply left over from the old days.
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Bob Kelly III
Ranch Kid from way back,.... that got Old !
somewhere along the line in years gone by I got ahold of a big roll of solder.... which is the worst solder I ever tried to use on ANYTHING !
it's a rosin core solder but it absolutely will not stick to anything not even copper ! I have no idea what that stuff is but take it from me there is solder that simply does NOT work worth a darn ! HAHAHAH!
.....unfortunately I still have some... it's all I have and I should throw it out but know it's better than nothing ....maybe !
.....
Bob.......
it's a rosin core solder but it absolutely will not stick to anything not even copper ! I have no idea what that stuff is but take it from me there is solder that simply does NOT work worth a darn ! HAHAHAH!
.....unfortunately I still have some... it's all I have and I should throw it out but know it's better than nothing ....maybe !
.....
Bob.......
This has been my choice of electronics solder for decades. Low melting point. I prefer smooth and shiny wetted joints over incomplete grainy joints.
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I too have a life time supply of solder. I bought a big roll back in 1978 and it is fabulous stuff - the lead variety. Apparently the lead causes brain damage, but the modern silver stuff gives me headaches!!
