Mystery Door Connector
Thread Starter
Member
Joined: May 2006
Posts: 77
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From: Australia
300E
Mystery Door Connector
So I was working on my car door lubricating the scissor lift and door check when I noticed a 2 terminal plastic female connector hidden inside the door. It’s not connected to anything and I can't see anything it can connect to. When I tested it with a multimeter is produces a closed circuit pulse exactly once a second like a clock. When the ignition is turned on it then produces 12v. Does anyone know what it is? Oh and my 87 300E was never fitted with a factory alarm.
Thread Starter
Member
Joined: May 2006
Posts: 77
Likes: 0
From: Australia
300E
Yeh I know what you mean, you'd think that was it but it doesn't explain that it turns on when the cars running and pulses when the car is switched off? And it is exactly the same with the doors open or closed? Also my car doesn't have a courtesy light down there.
MBWorld Fanatic!
Joined: May 2005
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
It will have power on one side at all times as the circuit is broken by the door switch via the earth lead.
What voltage do you see when it's pulsing and do you see a voltage across the the wires or are you measuring from each wire to earth?
Thread Starter
Member
Joined: May 2006
Posts: 77
Likes: 0
From: Australia
300E
Hmm this is very odd. The pulse voltage was less than 1volt and I was measuring across the two wires. I just think it's strange that MB would intall the wire but no light. Could someone tell me where the light is loacted exactly as it's not on my car and the Mercedes catelouge does not show any door lights for the 300E as you can see below.
MBWorld Fanatic!
Joined: May 2005
Posts: 2,494
Likes: 17
From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
Hmm this is very odd. The pulse voltage was less than 1volt and I was measuring across the two wires. I just think it's strange that MB would intall the wire but no light. Could someone tell me where the light is loacted exactly as it's not on my car and the Mercedes catelouge does not show any door lights for the 300E as you can see below.
USA wiring diagrams designate these as "E17/" and they are connected to the interior lights that operate when the door is open.
Is one of the wires red, and is this where you read 12 volts to earth?
Most manufacturers make wiring harnesses for all possible options, so you may find connectors that aren't being used.
