fast87t2

iTrader: (1)

So I picked up a Used MS1 off the forums, upon initial inspection I noticed that the builder or previous owner had smoke checked D10 and ran jumpers due to the fact that they blew the connections on the board. what would cause that? and is there a way I can check to make sure they did not smoke check anything else?
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so my question regarding that is I plan on buying a new diode and replacing it. is there a better way other then running jumpers to complete the circuit?

next part is I was told it was pulled from a running rx7, now I have to assume the person was not running a BAC valve due to the lack of PWM IAC mod, so I plan on adding that, but should I just remove the whole additional VR circuit and redo it considering the craftsmanship and the fact that I have no room to do the e-fan mod? or is it possible to run the ZEAL board on a MS1? and if I run the ZEAL do I still need to do the Relay control mod to run a e-fan or can I use one of the general purpose outputs on the zeal?
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lastly I tried cleaning the board with isopropyl alcohol ad as you can see it still looks awful. is there a better cleaner? or a better process?
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thanks for any advice and input.
-Joe

Aaron Cake

iTrader: (1)

Um, yikes

That is very sloppy work. Looks a bit like acid core solder was used?

To remove the flux, get some flux remover from a local electronics store. Comes in a spray can and dissolves flux very quickly.

Destroying D10 means that at one point the 'Squirt was connected backwards (maybe battery connected backwards at some point?) or a LOT of current was drawn from the 12V section of the board (after D10, 12V stepper connection).

D10 is there as part of the reverse polarity protection. While not required, it is best to be reinstalled.

Speaks volumes of the seller that the diode was fried, yet just replaced with a jumper. I can see how someone would install the jumper if they just needed to be back on the road but they didn't go back later and reinstall the diode.

Is the 1N4148 beside the jumper also broken?

Can you let us know what those electrolytic capacitors are on the VR circuit? None of the values in that circuit are electrolytic sized values.

I'd replace that circuit, with a Zeal as you like. Because as you suggest that is convenient since it has spare I/Os which can be used for the fan.

Overall that board looks very sketchy. Perhaps just because of the flux but I'd go over it with a magnifying glass very carefully after it is cleaned up. Fix any poor solders, check components that might look questionable.

Even then I'm not sure I'd trust some 400HP turbo car to it. NA, sure.

fast87t2

iTrader: (1)

1N4148 tests good but it also appears that D12 bit the dust also. I have gone through the power circuit checking every component with a DMM, But I am unsure how to check MOV1 (surge absorber 20MM 22V 2000A).

One of them was .33uf, used in place of the Tantalum Cap, ( which finding seems to be very difficult) the other was .01uf ( odd thing was he had one polyester and one electrolytic cap)

I ended up just removing the entire circuit and rebuilt it using the resistors and chip and a few of the caps, but I cannot seem to find a Tantalum cap to replace the electrolytic cap, digikey has none in stock.

Is the electrolytic cap usable in that place?


well its not a 400hp turbo but It will be running a 6-port turbo..

Aaron Cake

iTrader: (1)

No real easy way to test without a variable power supply. But the MOV won't have failed anyway.

The electrolytic will do in a pinch as it's just filter. Make sure though that the temp ratings are suitable for automotive use.

I would be very wary of using that ECU until it can be proven reliable.

Well, personally I wouldn't use it at all.