trouble shooting from the ground up

Hi

I have started building a Huxley using Sanguinololu electronics, one day my little brother came into my work space and covered everything in hand soap, which I only noticed after coming in and switching on the electronics to test the motors, anyway the board no longer works and I was hoping some one could tell me what and how to test it to determine weather its a new parts or new board fix.

any help would be appreciated

p.s. i only have hand tools and a multimeter for testing because test gear is expensive

Clean

1) disconnect everything, pull out modules and 644p/1284p chip that aren’t soldered in.
2) clean off all the soap... not sure of the best way to do this, but probably an isopropyl alcohol bath
3) dry thoroughly, leave in hotwater cupboard for at least 72 hours

Test

Plug the board into the computer without modules and 644p/1284p, the computer should still recognize the board as a serial port. As long as the FT232RL chip is working.

If this is working unplug it and plug in the 644p/1284p, plug it into the usb again. Can you connect to the board using pronterface or what ever host you used to use. If you cant its probably a dead 644p/1284p.

If it works plug in your thermistors and check you can read them. Still good? unplug from usb and wire in the power supply, turn it on, does the led turn on? If so, plug in usb and recheck you can connect. If you can turn it off and plug in the hotend and try that also... And HBP (if you have one)

Still ok?

Turn off, plug in stepper modules one by one and test that steppers move.

If all this work, you should be up and running again, or at least worked out whats dead.

Hi,
I used to work for a company where our electronics got occasionally drenched in salt water. What we did was to rinse thoroughly with lots of distilled water and then dry immediately after. If you don't let the water sit there for a longer period you won't get any corrosion to speak of. I suggest using a soft brush an rinse until you get no foam/bubbles.
A hair dryer will work fine for getting rid of the exposed water (it will blow underneath components) and then do as the above suggests, let it sit in a warm environment for a day or so.

/Jan

thanks for the responses,
After a little elbow grease and lots of pluging and unpluging of usb cables i seem to have almost everything working again, steppers still playing up but they were doing that before, so thanks again and perhaps this post can help other in the future