75 Eldorado power antenna will not go up or down

[ghhatley]

My power antenna doesn't go up so I wanted to remove it and check it. The unit seems to be hidden down in the passenger side lower front fender. Any suggestions on getting it out? Anyone have a wiring diagram? Can it be checked without taking it out?

[guyrobert]

It is probably the nylon cord that makes the antenna go up and down. They get old and break.
You will have to pull the antenna to replace. should be 2 bolts on the upper inner fender and one that you will need to get underneath the car to reach.

[Scot Minesinger]

Before you remove it, have you tried to power it from the battery directly?  The wiring in the 71-76 Cadillacs is not comparable to other years, especially the 75 and 76.  It is not really straight forward and you will need to look at wiring diagram to check this.

The antenna can easily be checked without removing it.  There is a plug connector adjacent to it.  The wiring diagram is in the shop manual.  the shop manual in 1975 is in two parts.  Need the brown 1975 supplement to the 1974 manual and the 1974 manual.  $50 on e-bay will buy these and it will be your best investment if you have not done so already.

Enjoy your Cadillac!

[ghhatley]

Thanks for the responses I'm going to work on it today. Who restores these things?

[cadillactim]

I would suggest you remove the antenna before testing it because if you get it to go up but it won't go back down, then you have to cut the mast off to get the antenna out of the car.

As mentioned earlier two bolts at top of fender and one larger bolt behind front tire in wheel housing. Be sure to remove the antenna cable and unplug wire connector.

Once out, ground the antenna body and put battery voltage to BLACK wire. Antenna should raise all the way and shut off. Then put voltage to WHITE wire and antenna should lower all the way and shut off.

If the antenna pass both of these tests, then put voltage to GREEN wire and antenna should raise 6-12 inches and stop. Just apply voltage to white wire again to lower it.

If the antenna doesn't work properly with these tests (or slips and won't raise all the way) then it needs rebuilt. If it does pass these tests you need to do one more test with an ohm meter. Apply voltage to GREEN wire and let antenna raise the 6-12 inches and shut off. Then take ohm meter and connect the leads to the GREEN wire and RED wire. There should be continuity. If not, then limit switch is bad in antenna. If there is continuity then antenna is okay.

If antenna will not work when connected to car harness, but works as just tested, then you could have a bad antenna relay.

I rebuild these antennas if yours is bad.

Tim

[TJ Hopland]

Once you get the air ride compressor out of the way I don't remember it being too hard to get to the antenna.    If you are not concerned with original appearance aftermarket units are much smaller so they can easily be installed in the same location without having to drill or cut anything.   I think they run about $50 at parts stores.   I have had one on my 73 or years and it works fine.   I'm sure an expert can tell the bezel is not 'correct' but it looks and works like a radio antenna to me which is whats important.   

[ghhatley]

The antenna works on the black and white wires outside the car but not inside the car. Does it need a rebuild or a new relay? Where's the relay and is it testable? I've ordered a tech manual but while I'm waiting I'd like to get this fixed. 

[Caddyjack]

the relay is on the passenger side floor, up at the firewall behind the carpet.

[ghhatley]

I assume this is the relay? The red or pink wire has been spiced and replaced. I messed with it and still nothing so does anyone have a working relay they'd like to sale?
Any idea what those cut wires are?
They're yellow, orange and green

[ghhatley]

Relay picture

[cadillactim]

Make sure the relay is grounded good. They are common to go bad. I do have them rebuilt for $35 with exchange. US shipping is $8. If you want one you can email me or call 864-348-7732.

Tim

[ghhatley]

Thanks Tim I'll probably be doing that. Any idea what those cut wires might go to?