Possible fuse issue?

[Hunter649]

Hey all,

First time poster but been lurking here for a while. I've just bought a '77 280SE a few weeks back, while driving it last night the radio, antenna motor, central locking and dash clock all stopped at once. I assume this is some kind of fuse issue but wanted to get some more experienced insight before I go pulling things apart and investigating the strange clicking coming from the glove-box region.

Thanks!!
Mitch

[daantjie]

Locks are vacuum operated so that has nothing to do with fuses.

[revilla]

Hi,

Probably a previous owner upgraded the locks to selenoids, which would explain your situation.

Here's the fusebox diagram. Probably fuse 1 I presume. Pay attention that sometimes the fuse itself is fine, but the problem comes from dirty contacts right at the interface with the tabs. Try moving it in circular motion and/or spray some contact cleaner and rub with a plastic soft brush (never metal). Guarantee problem is that. It happens all the time with these W116s and many other models from that era.

Please keep us posted.

I hope that helps, and welcome to the wonderful ownership Mercedes world.

[revilla]

This might help too.

https://m.youtube.com/watch?v=QAq0t_Fmb7A

It isn't uncommon to find fuses values in the wrong location.

It's a good opportunity to check (or replace) all that.

Hope it helps.

[Hunter649]

Hey all!

Appreciate the responses, it was absolutely fuse #1, quick and easy fix when you know what you're looking for.

Thanks for the assist and the warm welcome 😊

[ptashek]

Hey all,

First time poster but been lurking here for a while. I've just bought a '77 280SE a few weeks back, while driving it last night the radio, antenna motor, central locking and dash clock all stopped at once. I assume this is some kind of fuse issue but wanted to get some more experienced insight before I go pulling things apart and investigating the strange clicking coming from the glove-box region.

Thanks!!
Mitch

Welcome!
A fuse also wouldn't pop for no reason. The fuse is blue, indicating it's a 25A rated one, while circuit #1 needs a white 8A fuse. Try disconnecting things on that circuit one at a time, see how power draw looks like. Could be a dead short to ground somewhere.

I recently had a similar issue on my W124 - one day it just randomly blew out a couple 25A fuses. Turned out to be a failed alternator voltage regulator, outputting 17V instead of 14.2V. Might be worth a check too.

[MrBenz]

Disconnect antenna plug in boot
Mine was blowing fuse - found antenna motor burned out