I've ran into a bit of a problem that at first was intermittent and is now constant. My condenser fan no longer turns on and for some reason won't power even with other fans. Swapped out relays and tested power at the fuse box, everything is perfect. Tested for power at the condenser fan connector and it has over 12 volts when you hit the AC button. However with a fan plugged in I get nothing. I considered the possibility of a bad ground, even though I checked the voltage using the ground terminal in the connector, so I cleaned a different spot and moved the ground. Still nothing. Both fans I have tested with cabled directly to the battery and they power up.

 

Maybe poor contact of pins in the connectors. Or damaged pins.

 

i considered that so I even went as far as making a jumper harness with blade terminals to push into the other connector and checking voltage at the other end.

 

Add car information your first post.

-----------------
Unplug the fan connector.

On the fan side of the connector, do you measure continuity to body ground on the ground pin using a multimeter.

On the wire harness side,what voltage do you read at the power wire pin?

 

Put the minus end of your meter on the battery (-) and leave it there. Unplug the compressor so you don't get an overpressure due to fan not running. Plug everything else in. Turn on the A/C. Measure voltage at both leads of the fan to battery - (ground). One should be 12 volts and one zero. If both are zero there is a problem in the power source side of the circuit. If both are 12 volts there is a problem in the ground side of the circuit. You can then measure other places along the line to see where the voltage is being lost.