WIERED ECU...

[zimbali]

I opened an ECU -> all the board and its components were sank in a pinkish kind of gum. Is it usual? and if it is, how to remove that stuff from the board safely?
(Nothing was clear with that gum, I could only see a pink plane in front of me).

Any help would be appresiated.


Cheers


You can live in your car, but you can't drive your House!

 

[TheBlacksmith]

That gum has 2 or 3 purposes; water proofing/resistance, heat conductivity to the case for cooling and to keep unauthorized people from changing components/calibrations and increasing emmissions. You may be able to "melt" it out with a low temperature oven, suspend it upside down over a pan and slowly increase the temperature until the gum melts or you ruin the ECM.

Blacksmith

 

[zimbali]

Thanks Blacksmith

That was a good idea, but I'm not sure if it's something MELTABLE!! I don't know why I think so, just a feeling.

And is there anybody having any idea of how popular is this kind of covering the boards in ECUs?


Cheers


You can live in your car, but you can't drive your House!

 

[zeitghost]

It's known as conformal coating and is used to keep the board waterproof.

There is stuff to remove conformal coating, but I think it's a fairly aggressive chemical.

Once you've removed it, you can see the components etc. but you'll have to recoat the board to put it back into use.

I would expect most critical boards (like ECUs) to have conformal coating.

Non critical pcbs (like car radios etc) won't have it because it's a fairly expensive operation. (i.e. it costs about 5 cents a board at a guess).

rgds
Zeit.