Why is it suggested that one disconnect the battery when removing and replacing the power antenna on a W140?

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Richard Seaman
1982 300D Turbo 198k
1987 420SEL Sold
1993 400SEL 123k
MBCA Desert Stars

You could induce a short and blow the ant. fuse itself or perhaps even one of the stereo fuses.

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1986 300E 5-Speed 240k mi.

Noted mention of the antenna fuse...just where is it? The radio comes on but the antenna doesn't extend. It worked at the dealers until I signed the papers!

'93 190E replacing wife's totaled '89 190E
original Becker with 6 casette holders above.

Paul,
The antenna fuse in my 1993 400SEL is located in the main fuse box under the hood. To check if the antenna motor is running have someone turn the radio on and off while you put an ear near the antenna. If you hear the antenna motor running there are a number of things that could have failed inside the antenna assembly. I will elaborate on those after you check the above and report back..

I'm not sure what model antenna your MB has in it.

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Richard Seaman
1982 300D Turbo 198k
1987 420SEL Sold
1993 400SEL 123k
MBCA Desert Stars

Regaining sanity after 3 dayss of virus/format C:/reinstall/

Antenna fuse under hood is ok. Verified by meter and by examination of associated items powered by the same fuse.

Antenna is probably ok. I removed it, manually rotated the motor to extend the shaft, upon installation it promply retracted itself.

Which tells me what is missing is the signal
from the radio which requests the extended shaft.

I'm thinking the single wire is the extension signal wire but don't know if the radio puts out 12v or a lesser voltage. No voltage is present when the ignition and radio are on.

I'm impressed with the inclusion of 900 mHz cell circuitry for a car telephone. I'm dissapointed that Motorola connectors are not used (but not surprised) so that I could stick in an 8-ball antenna to quickly get my talk stations back.

In 123's and 124's the antenna gets a constant 12V so that it can retract when the ignition is turned off. It also has a separate wire from the radio that supplies 12V when the radio is turned on. The logic board in the unit tells it to raise when it gets the 12V and lower when it is turned off. There is some additional circuitry to adjust the height of the antenna from a switch on the dash.

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Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe

My original 1989 190e had a dash switch but this 1993 does not.

I have been fixing the little things not working, like the ash tray drawer which wouldn't stay shut, when the radio antenna quit. Now that the problem seems to be at the radio, for which I thank you for your help, I will again remove the ash tray and see if that antenna wire got pinched or otherwise altered during the ash tray fix.

Getting closer making it into a newish car...I can't stand to have anything not working as new.

i've got a '95 140 and my antenna is built into the glass.the antenna goes up when i'm using the phone.lift up your first part of the centre console and in there is a switch for the phone.with the switch ON, the antenna will go up as soon as the ignition is turned on.hope this helps, it took me a couple of days to realize these were tied together.if in doubt :read the manual!



okay just came back to this post.what the hell was i thinking?talk about coming into a conversation halfway through!i guess it's time for bed,anyway my radio has a built in antenna and the one that goes up/down in the back is for the cell phone.goodnight!

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'95 s500 (bought for wife but can't bear to share!!!) 125kms
'92 legend 180kms
'88 tbirdturbo(fantastic car-only regular maint.)120kms
'87 mustang gt(gone)
'86 tbirdturbo(gone)
'85 mustang gt(gone-but not forgotten)

No manual with the car.

Removed the Becker radio and all connectors look connected. Could not identify the same blue wire which was evident at the antenna in the rear. Is there a site which shows the wiring/connector diagram for the radio. I still need to ascertain whether the problem is in the radio or the wiring.

Blue wire is covered by black plastic. Why ? Beats me.
Hope this helps.

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J.R.

I had a similar problem with my antenna and upon inspection, there was corrosion on the male side of the plug connection. I cleaned off the corrosion and it worked again.

have same problem, motor is dead but gears and mast look fine and extend mast by turning the gears manually... so how to check if the motor is burnt out or if some connection is missing??

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1993 500SEL

This is an old thread!

If you look at the motor, you should see two wires leading to it. If you put power and ground to those wires, the motor should turn.

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Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe