S420 Antenna problem
 

The antenna in my '95 S420 goes up whenever the ignition is on even if the radio is off. What can I do to make it only work when the radio is on? I don't see any switch in the dash like older models had.

It is set up that way for the cell phone. If you are not using it for the cell phone then you then iit could be wired to the amplifier turn on instead.

Scott@lajollaaudio

There is no cell phone in the car. Is there some switch on the amp to control the antenna?

If a cell phone was never installed in the car, there is nothing else that would keep the antenna mast extended, except a failure in the system. Chance are it's just a stuck mast, the mast is available seperately. Other possibilities would be a blown fuse or the antenna motor itself failed in some way. Never seen a radio itself cause a failure like this. There is no other control over the antenna, no seperate switch on the amp or radio. On the factory phone, as has been discussed, there was a seperate power switch on the phone (either handset or cradle) that needed to be switched off, otherwise the phone remained on and the antenna stayed extended. So if there is no phone handeset or cradle in the center console (or indash controller in that small center compartment above the center dash vents), then it has to be a failure in the system.
Gilly

There is a phone jack in the center console for a phone. What wires can I connect to simulate a phone being off?

I was only trying to impress upon you the importance of being absolutely sure there is no phone equipment in the car, because this would be the most common cure for a complaint like this---shut off the phone!
If you are sure there is no phone equipment in the car, such as a cradle or in dash controller, then forget this whole phone thing.
It is common for the mast to seize. In over 80% of the mast not retracting complaints I get, the cure is the replacement of the mast.
You can have someone turn your radio on and off while you put your ear to the rear fender in the area of the antenna and listen for the motor to run, or attempt to run, that will tell you if the antenna motor is being switched on and off. If the electric motor just runs and runs without effort, the antenna motor will probably need replacement. If it seems to run, then slows down (labors) then quits, the mast itself is probably just seized and can be economically replaced.
Gilly

[QUOTE]Originally posted by gillybenztech
[B]If a cell phone was never installed in the car, there is nothing else that would keep the antenna mast extended, except a failure in the system. Chance are it's just a stuck mast

From what I read of the original post, it is not a question of the antenna remaining extended, but rather that it extends every time the ignition is switched on.
Same happens to be true of my 450SEL.
A royal pain-in-the-neck at car washes.
You must track down the power supply to the antenna.
It could be incorrectly wired at the head unit.
Who am I to talk, I have not fixed mine yet.
Colin

You should be happy......
 

The power mast on my 300SE doesnt come up at all. Even when I turn the phone on, it still wont go up. I dont listen to the radio much, so I just leave it like it is!