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GMMike
09-17-2007, 08:26 PM
Can't I use a 9 volt battery to energize the relay to see if it clicks? If so how? Thanks.
tenspeed
09-17-2007, 08:31 PM
How about using that 12 volt battery under the hood?
tenspeed
09-17-2007, 08:34 PM
http://www.1728.com/project3.htm
GMMike
09-17-2007, 09:07 PM
Man long read :P I just want to know if I can test my relay using my 9 volt batter, if there is a way. Is using my car battery easier?
rixGAphx
09-18-2007, 10:51 AM
A relay energizes via a small electromagnet.
One that's designed for 12V *might* work with only 9V; might not.
So if you test it with 9V and it 'clicks', then that portion (the input) side of the relay is good.
But if it doesn't click, then it might still be good but the 9V isn't powerful enough to cause it to function; so the test is inconclusive.

To so test, you would identify the two input terminals, and pass current across them using jumper wires from the power source.

As tenspeed said, it's prolly just as easy to connect the two leads to the car battery as to a 9V.
And connected to the car battery's 12V, the click/no-click would be conclusive (relative to the input side of the relay; tho there could be something ELSE wrong inside the relay).

Hope this helps,
-Rick