Hello again,
I was replacing my power antenna in my 240 and decided
to test the antenna that I had pulled from the salvage yard.
The antenna has two wires and a ground. I gave the two wires
power from the fuse box and grounded the ground wire.
The antenna extended fully and then clicked two or three times
(it did not stop when it extended fully).
Then I removed one of the power wires and it began to retract
than stopped with about 8 inches still needing to retract.
I attached the second wire and it extended again, but when
I removed that same wire the antenna retracts with about 8
inches still sticking out.
Also, does the antenna also ground where it is attached to the body
of the car?

Also, do all the fuses receive 12 volts on the left of the
fuse and then the fuse lessens the volts as it passes through
the fuse?

Any advice would be appreciated.
Joseph

You may need to free up the sections of the mast for smoother operation. They get slightly bent or corroded. Dan

Easy one first - there is no measurable voltage drop across a fuse, unless somethng is wrong with the fuse. Not worth considering.

Antenna ground. The ground wire on all my 240's is attached to a body seam flange nearby with a short sheet metal screw. It does not grond via the metal mount piece.

Third. The antenna motor is shut off when there is too much resistance in moving the antenna, whether going up or down. There is a device that measures this, and I don't know how it works, maybe with a sudden spike in current draw.

So, going down it meets with too much resistance too early. Something similar with the going up problem.

The mast and nylon gear can be removed, but I don't recommend that. It's a very PITA job to get it back, if possible at all. I did it but I had to disassemble the entire power unit to do it and it took three hands to wind up the spring, hold the nylon gear in place, and close up the housing. A new one is really easy.

I would suspect that the grease inside the area where the nylon gear gets would up inside has gotten hardened with age, thus creating resistance to motion.

Good Luck,

Bob

:>)

Bob,
Thank you for your tips.
It makes clear thinking that the antenna stops
in either direction when there is resistance.
But when this one went up, the motor didn't stop on
its own, the gears were clicking (sounded like they
were jumping one another). Maybe the indicator that
there is resistance is broken or dirty. I am going
to open her up in the am and get my third hand out.

Maybe on the retraction there is a sensor that tells
it that the motor has wound fully up, but since it jumped
gears on the way up the sensor tells it too soon on retraction.
I will let you know what happens.
Cheers,
Joseph