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Resolved 1G TCU capacitor sizing?

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EC17PSE

Freelancer
5,931
3,562
Nov 1, 2008
London, UK, Europe
So I'm working on my 1g finally and ordered new exact OEM capacitors. Has tech come along way since as the OEM one is huge compared to the new one but its rated to the same spec? Check out the pics but its almost 4mm smaller but exactly the same specification. I know back from 90's etc things do change but wanting to be sure its all good and I'm not needing a bigger unit for better temp control as I know it has to handle some temps for its job.

Old is big 10+mm and new is 6+mm

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If it's the same capacitance, temperature rating, and DC voltage, the change in size is just due to newer material technology on both the conductor and insulator fronts.

Generally they maintained their fatness by allowing for increased voltages, but 50V DC nowadays allows for some pretty compact aluminum electrolytic caps. I assume both are 105C temp? Higher temp handling also generally means fatter caps.
 
If it's the same capacitance, temperature rating, and DC voltage, the change in size is just due to newer material technology on both the conductor and insulator fronts.

Generally they maintained their fatness by allowing for increased voltages, but 50V DC nowadays allows for some pretty compact aluminum electrolytic caps. I assume both are 105C temp? Higher temp handling also generally means fatter caps.
yup on the back it says 105c as I'm pretty sure i checked for that also. I'm not electronics expert but its crazy how much smaller it can be for the same product!
 
There are other factors in play, such as ripple current handling and the length of time they can survive at max temp. What's the exact PN of your new cap there?

Looks like 50YXF47MEFC6.3X11? I think for the purposes here, it should be fine.

If it makes you feel better, there are 3 variants of 50V 47uF general purpose caps in 10+ size on mouser (digikey should be similar). There are 38 variations in 6.3mm size :)
 
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There are other factors in play, such as ripple current handling and the length of time they can survive at max temp. What's the exact PN of your new cap there?

Looks like 50YXF47MEFC6.3X11? I think for the purposes here, it should be fine.

If it makes you feel better, there are 3 variants of 50V 47uF general purpose caps in 10+ size on mouser (digikey should be similar). There are 38 variations in 6.3mm size :)
And there was me thinking 1+1 is 2 LOL, let me check the actual part number to be sure. I did just go by the big letters LOL so if i pulled the buy faster then i should the whoopsie.
 
There are other factors in play, such as ripple current handling and the length of time they can survive at max temp. What's the exact PN of your new cap there?

Looks like 50YXF47MEFC6.3X11? I think for the purposes here, it should be fine.

If it makes you feel better, there are 3 variants of 50V 47uF general purpose caps in 10+ size on mouser (digikey should be similar). There are 38 variations in 6.3mm size :)
on the side its got 3m1947 105c pet
 
You'll be fine regardless. The most important change is the new ones don't leak like the originals.
Sadly yours has and the solder around it has become porous. Hopefully the traces haven't failed and the voltage regulator with them. TCUs have this nasty habit of dumping 12v on the 5v rail when the cap leaks.
 
You'll be fine regardless. The most important change is the new ones don't leak like the originals.
Sadly yours has and the solder around it has become porous. Hopefully the traces haven't failed and the voltage regulator with them. TCUs have this nasty habit of dumping 12v on the 5v rail when the cap leaks.
Its not as bad as some other pictures i have seen but still bad none the less. I will be cleaning it up and de scaling it with methods i have found online. I will see what happens once its all back together and hope i did a good job on it all.

Dont know if you seen my build thread update on it but this is the cap that leaked and the tcu around that area. Some other corrosion on the parts but mostly looks ok and surface like. Can only try and hope for the best 😉
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Yep, that's the critical area that far too often kills the TCU. The green transistor there is part of the voltage regulator and white hybrid IC on the other side of the cap has the logic to drive it.

The yellow sleeved capacitors don't usually leak and the two bright orange caps are tantalum ones that when they fail they usually explode.
 
New capacitor went in and all seems ok now its cleaned! Its not mega hard to do just a bit of time and hands and calmness to do it! Even though the capacitor is smaller its still the same spec and rating so thanks modern technology for smaller parts.

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