Replacing a power antenna

I’m replacing a power antenna on a 1990 Buick Lesabre since the original antenna is partly broken off. I ordered a universal antenna online so just waiting for it to arrive.

The original antenna has a 3-wire plug going to a factory wiring harness and I’ve been told I need to get a test light so I can figure how which wire is always hot, which is switched and which is the ground.

When I first noticed the original antenna had broken off I unplugged it from the factory wiring harness which I had forgotten I had done. So I plugged it back in ( just to make sure that’s the place I plug it back into) and the antenna motor starts running even though the ignition switch is off.

Why would the antenna motor be running with the ignition off?

The antenna would extend when the ignition and radio were on. If either were turned off, it would retract. If you remove the old antenna and clean out the housing a new mast may be all that is needed since the retracter appears to work.

Okay thanks I guess that explains why the antenna motor would be running with the ignition off. I had thought about possibly just replacing the mast but I wasn’t sure I knew how to replace it or if I could even find a factory replacement mast so I ordered a new antenna.

Replacing the Mast on most antenna’s is pretty easy. And you don’t need a factory replacement. There are aftermarket Masts that work fine.