On 2/9/2020 8:38 PM, Adam wrote:
On Sun, 09 Feb 2020 20:06:16 -0500, Tom Biasi wrote:

On 2/9/2020 7:31 PM, Adam wrote:

My car's blower motor relay may be bad (or the cause of noisy fan). So
I found the following video...

How to Test a Relay the Correct Way
https://www.youtube.com/watch?v=ire7vyDqelg

However, I don't have a cordless drill battery (used in the video).
Will the following battery charger...

UPG D1724 Sealed Lead Acid Battery Charger (6V/12V Switchable Single-
Stage With Alligator Clips)
https://www.amazon.com/gp/product/B0...c_act_title_1?
smid=A10QFO4IXVZNRN&psc=1

work ? Other frugal ideas ?

An automotive cube uses 12 volts. Any 12 volt DC source will see if the
coil pulls in the contacts.
There is much more to checking a relay properly.
Pull in current, dropout current, contact resistance, and more.
But if just want to see if you can hear the armature pull in that it
will do that.

According to the video, I think I also need to check resistance.

Will that battery charger on Amazon work ?

Any 12 vdc source will work.
to check coil resistance you need an ohm meter.
The relay in the video has a diode.
So ohm meter polarity is important.
In a proper test the diode characteristics would also be checked.