What is this 2-prong female receptor behind the ash tray for? - PeachParts Mercedes-Benz Forum

edge · #1 12-03-2009, 03:11 PM

I've got my stock stereo out and I notice a 2-prong female receptor underneath there is unplugged but I can't find where it should be plugged in? Any ideas:

Pictures in post #32 of thread: 300D heater is either off or full blast?

funola · #2 12-03-2009, 04:56 PM

Does it have power on it? Cig. lighter? Make sure cig lighter fuse is good and ign key is on before checking for power.

dieseldan44 · #3 12-03-2009, 05:39 PM

Thats where the 12V for the cig lighter connects to the moving ashtray cover.

Look at the back of the ashtray cover you took out. You'll see the contacts.

You should see 12V there with the ignition on.

dd

MBeige · #4 12-03-2009, 07:27 PM

Quote:

Originally Posted by dieseldan44

Thats where the 12V for the cig lighter connects to the moving ashtray cover.

Look at the back of the ashtray cover you took out. You'll see the contacts.

You should see 12V there with the ignition on.

dd

The one for the back of the ashtray has a different type connector (perpendicular flat prongs, one ground/brown, one power/red).

edge · #5 12-03-2009, 07:44 PM

Thank you, it was perplexing as it was connected to a part I had removed!

edge · #6 12-03-2009, 08:52 PM

Quote:

Originally Posted by MBeige

The one for the back of the ashtray has a different type connector (perpendicular flat prongs, one ground/brown, one power/red).

Then any idea what it's for? I'll check in the daylight.

JHZR2 · #7 12-03-2009, 08:54 PM

Those two, IIRC, are illumination and switched.

Be careful and work with a multimeter back there. I shorted a bunch of fuses because one line reads neutral when the lights are off, and 12V when the lights are on.

It is misleading because you dont get 0V ltl or no reading - it shows up to enable a constant 12V to show + or -12V depending upon your leads, and the lightswitch position.

But again, I believe that one of those is switched illumination and one is either constant or switched 12V.

edge · #8 12-03-2009, 09:33 PM

Quote:

Originally Posted by JHZR2

Those two, IIRC, are illumination and switched.

Be careful and work with a multimeter back there. I shorted a bunch of fuses because one line reads neutral when the lights are off, and 12V when the lights are on.

It is misleading because you dont get 0V ltl or no reading - it shows up to enable a constant 12V to show + or -12V depending upon your leads, and the lightswitch position.

But again, I believe that one of those is switched illumination and one is either constant or switched 12V.

Ohhh? How come they are not plugged into the oem radio anywhere? Today I installed a new Alpine CDE-9872 head unit, wired with spade connectors:

oem brown wire to Black ground Alpine
oem black female spade connector to red ignition switch wire Alpine
oem black wire (cut before fuse wire hardwired to stock radio) to Yellow battery wire

connected antenna jacks
connected 4 speaker wires tested with battery for proper connection.

Still my Alpine doesn't turn on! What am I missing? Do I need a fuse between the battery and the Alpine? I taped the ground wires together, shound I squeeze spade connectors on the ground wires. Or do I used one of these 2 prong connected? Confused...

Help, thanks.

MBeige · #9 12-03-2009, 09:57 PM

Quote:

Originally Posted by edge

Then any idea what it's for? I'll check in the daylight.

Same answer I gave you at the other thread - must be the connector for the temperature sensor. It has the same type of plug, but as I mentioned I don't recall if it's the same color combination of wires.

Could also be for one of the vacuum switch over valves. That could probably cause the main problem you're having with the climate control unit (heat/no heat).

JHZR2 · #10 12-03-2009, 10:29 PM

Quote:

Originally Posted by edge

Ohhh? How come they are not plugged into the oem radio anywhere? Today I installed a new Alpine CDE-9872 head unit, wired with spade connectors:

oem brown wire to Black ground Alpine
oem black female spade connector to red ignition switch wire Alpine
oem black wire (cut before fuse wire hardwired to stock radio) to Yellow battery wire

connected antenna jacks
connected 4 speaker wires tested with battery for proper connection.

Still my Alpine doesn't turn on! What am I missing? Do I need a fuse between the battery and the Alpine? I taped the ground wires together, shound I squeeze spade connectors on the ground wires. Or do I used one of these 2 prong connected? Confused...

Help, thanks.

Did you pull an OEM radio?

The easiest way that Ive done it is to tap into the power provided by the OEM connections. Switched is the lead from the wire that goes to the ashtray.

I have to think about how I did the rest of it. I think there is a +/- comng from the ashtray, a - that goes to the chassis, an antenna lead and the antenna.

In my 83 that had an analog radio, I had to run my own wire to the radio for constant. In the 85, it had a wire just like you showed. One was constant, one was illumination. Check them with a multimeter, if they show 12V like that, then use them like that, with the ashtray lead, and you should be good to go.

Sure youre not busting a fuse?

edge · #11 12-04-2009, 12:54 PM

Quote:

Originally Posted by JHZR2

Did you pull an OEM radio?

The easiest way that Ive done it is to tap into the power provided by the OEM connections. Switched is the lead from the wire that goes to the ashtray.

I have to think about how I did the rest of it. I think there is a +/- comng from the ashtray, a - that goes to the chassis, an antenna lead and the antenna.

In my 83 that had an analog radio, I had to run my own wire to the radio for constant. In the 85, it had a wire just like you showed. One was constant, one was illumination. Check them with a multimeter, if they show 12V like that, then use them like that, with the ashtray lead, and you should be good to go.

Sure youre not busting a fuse?

Yeah, I'm swapping out the stock Becker Europa. It was getting too erratic. It's weird because I pulled the wired as listed above from the oem Europa. The red wire (in a sheath with the brown ground) that I assume was a constant is actually a switched wire. There was no need for a constant on the analog Europa. The black wire that was spade connected to the back of the Europa is perhaps for illumination as it is 0v when off, 3.7v when switched on, then 6.8v with headlights on.

As for the 2 prong plug, it has blue and red wire connectors. The red is always on, the blue is switched on with 3.7v, 5.8v with lights on. The Temp sensor already has a 2 prong plug in it. I now assume that the 2 prong is for perhaps an better optioned radio than the Europa that was in there.

Thanks.

Jeremy5848 · #12 12-04-2009, 01:08 PM

There are two temperature sensors in the air box that take that kind of a plug. One is for the heater core, one is for the a/c evaporator. Could be either one.