Antenna Fun '83 300TD Wagon..
 

Hey folks,

I've got a working Hirsch bench tested antenna from a reputable dealer.

Why do I get +12V to pin 5 & 6 with the ignition off? They're only supposed to be activated with the switch. I pulled the switch from the dash and I get the same reading.

I get +12V at pin 1 with the ignition off which is normal.

Now I can't get the radio to turn on...fuse is good.

Help appreciated!

When you turn the car off, the antenna is supposed to go down. That is where the 12v with the ignition off comes into play.

Dkr.

Many years ago, I was presented with a 1983 300D that had experienced the original Hirschmann antenna being replaced with something else and the associated wiring and connectors having been destroyed. The approach I chose and the one I would choose in this case if I owned the situation is as follows:
For a definitive diagnosis and corrective action (if necessary), consider referring to, studying, understanding, and following the electrical schematic for the circuit.

Lol I I thought the guy above me was gonna get to some amazing point... Haha

Wow! Some real wizards on this forum...

See diagram 115 in the ETM:
https://www.startekinfo.com/StarTek/outside/12265/disc_2/program/ETM/83_300.pdf
From the diagram, it would appear that power is supplied to the switch from the radio. Possibly the radio has an internal fault.

Hirschmann Antennas
 

They're often only needing some cleaning and a new mast to work perfectly again .

The damned Foster boys keep bending the antennas in my graymarket '84 300TD, I need to replace it yet again .

I'm told the Uro brand replacement masts are worthless .

Originial ones are still available from Pelican Parts at a fraction of the deal co$t .

FWIW,
 

Any red wire anywhere in the entire car should, nee must be live at all times , the circuit # is 30 .

SOLVED!

In-line glass fuse behind stereo was blown. Replaced and everything works.

Antenna wires:

Pin 1 (blue) +12v

Pin 2 (green/yellow) Trigger (+12-lifts antenna, no voltage-drops antenna)

Pin 3 (brown) Ground

Pin 4 NC - No Connection

Pin 5 (black) NC-Medium Extention, Jumper to Pin 6-Full Extension

Pin 6 (black) NC-Medium Extention, Jumper to Pin 5-Full Extension

Over and out.

Thanks for the help folks!