Searching for relays and circuit breakers in my car

April 1, 2019 | By Staff


Where is the power feed to the power windows in my 1961 Ford Thunderbird?

I started my car and discovered that the power windows didn’t work even though they worked the last time I drove the car. I also have an issue with the heater fan motor not running.

I checked the fuses and replaced them all, but my manual says the power windows are not powered through the fuse box, but have relays and circuit breakers. If so, where are they, as I have been having trouble locating the circuit breakers and relays.

I bought a new fan motor and now have to install it; I also purchased a new switch panel for the heater, hoping that these would solve my problem.

If you can help me find the power feed it would be greatly appreciated. I have been a subscriber to Auto Restorer for many years, back into the 1990s.


The power lead to the window relay comes from the starter. Before doing the troubleshooting, obtain a wiring diagram and a multi-meter, and then familiarize yourself with the multimeter before going to work. Check each circuit that seems to be dead using the meter and look for loose and corroded connections. Clean all contacts and smear on a little white lithium grease to prevent further problems.

The front window circuit breakers are under the dash and hard to get at, and the rear window breakers are under the rear seat cushion on the floor, but they are not likely to be your problem. It is more likely that the windows aren’t working due to a faulty relay, which is on the firewall under the hood just to the right of the blower motor. Relays and the breakers are available new from Mac’s Antique Auto listed below.

The relay is there so the ignition switch does not have to take the full load of the window motors. Instead, they get their main current from the starter. People have been known to bypass the relays and just hook the windows directly to the ignition switch, but that is dangerous because the switch wasn’t made to handle that much juice.

In addition to checking the relays, I would take off the door panels, clean the window winding mechanisms and grease and align them, and make sure the motors are in good order. After all, they have been hard at work for over half a century, through rain and shine and constant door openings and closings. I would also check and replace the weather seals at the windows if required because they can lose their flexibility and become stiff, and will allow moisture into the doors.

If you need a relay or circuit breakers, call Mac’s. They sell the breakers for about $10 and relays for about $60.

Mac’s Antique Auto Parts

6150 Donner Road, Lockport, NY 14094