Pm3 does not power up by buttons

[Hans]

Has one ever come across the following?

My Pm3 monitor works fine when rowing and also when connected with a usb cable to my computer, but ..
it doesn't power on when just pressing the buttons ?

Thanks in advance,
Hans

didn't know what bumping a topic meant, so i accidently 'posted' an old message

[Citroen]

Have you tried dismantling it and cleaning everything on the bottom side of the circuit board with iso-propyl alcohol?

[Carl Watts]

Pull the board out and clean all the black stuff off the gold plated button contacts on the board as above.

If you have a really old PM3 it may be worth putting a new keypad in it as well. You can clean the keypad but the results may be temporary, recently I just moved to replacing the keypad on 2003-2005 monitors or high wear ones which are obvious as all the test is missing from the buttons.

[Hans]

Thank you Citroën for Your positive comments. Didn't expert that;-). Yes, i cleaned the 'gold' contacts and a little on the other Side of the board with ipa. Didn't work. Many thanks again.

Thank you Carl, i'll try once again with ipa. The contacts and a little more intensive the other Side of the board. If, what i expect that won't work, i Will buy, like you suggested, a new keypad. Thank you Carl.

[Carl Watts]

its rare to have all the buttons not to work. usually the menu back button fails first or you get some corrosion that takes out a couple of others as well.

Power it up using the rower and just pull the handle then try the buttons to see if they work.

If you pull off the keypad and there is green stuff on the back of it then its corrosion. Unfortunately the board uses very fine tracks and a few other mistakes that could have been improved on like not putting a test point in the middle of a track or at least using a teardrop contour to connect it to the track both sides. The PCB layout could have been improved on both the PM3/4 and the PM2, notably a series of vias should have been used on all the smd socket pads to help tie the pad to the board so it didn't get ripped off the board so easily.