2001 Jeep Grand Cherokee Limited AC fans not blowing

I've got a 2001 Jeep Grand Cherokee Limited 4.7L 8 CYL SOHC MPI 4 DR.
WAGON/SPORT UTILITY.

The AC seems to be working fine, but the fans aren't coming on so the
cold air isn't blowing out. I had somebody work on the AC before and I
think they messed up the wire harness that is below the dash under the
glove box.

I've run a multimeter on the red and black cables that go into the
whatchamacallit that I think is a sensor of some kind that's under the
dash. There isn't alot of voltage going across, but I'm not sure how
much should be. The "sensor" is made of aluminum and it's got
something like looks like spikes all over one side of it. I took it
out of the dash so it just hung by the wires and the air is blowing out
the hole where I took the part out when I tweak it so that the fans do
blow. I've got pictures of it that I can email to someone if they'ed
like to take a look at it.

Anyway, if anyone has any ideas I sure would appreciate it. It's a hot
summer and I sure do miss my cold air.