Relay problems

[mw52563]

Hi
I've been trying to fix a treadmill circuit board for what seems like forever.. I think it may have something to do with the relay. For some reason I'm getting a reading of 12v on both connection 1 and 2 which I assume is stopping it opening? I've posted some pictures below thanks for any help,
Regards Mike

 

[dr pepper]

That might be correct, the relay may have the - switched, meaning there will be a + to it ay all times, this means a mulitimeter will read + voltage on both coil connections, this is because your meter is measruing the + supply directly on on eof the pins, and through the coil onthe other, as most meters are very sensitive.

 

[Les Jones]

If are reading +12 volts with respect to whatever your reference point is on both terminals 1 AND 2 of the relay then the voltage between them is zero so the contacts should be open. Confirm the test by measuring the voltage BETWEEN contacts 1 and 2. Have you confirmed thet the relay contacts have not welded together by measuring the resistance between relay connections 3 and 4 ?

Les.

 

[Shoa]

take it off put signal voltage through 1 and 2 see if it clicks or you get a reading from 3 and 4 opening and closing continuity