eddieo45

I bought my 2000 C280 Sport with a cracked drivers side mirror. I bought the glass (2108100121P, I don't know if the P means anything) for about $100 less than the MB dealer wanted(BuyMBparts, Inc). Then the dealer wanted $110 to install it, so I brought it to my windshield guy. He had a hell of a time figuring it out, and couldn't get the old glass out w/out destroying it. He got the new one in, and it seemed to work fine, but doesn't get hot. I'm afraid that if I went to the dealer, I might still have had the problem, cause maybe the part is defective. It was new in the box, and Rusty at MBparts says I can send it back, but how would I get it out? Nobody seems to know how it can move but not get warm. I hate to go to the dealer after all, but what are my options? Any ideas?

JimPurdy

I don't know about the "P" either but the base part number is correct. Is there a 5 pin plug with 4 connections used on the back of the mirror? I have a repaired 2108106516 complete driver's mirror assembly that contains the mirror you mentioned. This mirror has the 5 pin plug assembly and did dim and heat when it was on the car. I can understand the mechanic's issue with replacing the mirror. It certainly is much easier when the assembly is off the car and you can look at the back of it.

eddieo45

yes, there is a 5 pin plug, which is plugged in (I assume if it wasn't, the mirror wouldn't move). I got a reply in another forum that suggested that there are other wires that must also be connected for auto-dim and heat, but I don't recall seeing anything but the 5 pin.

JimPurdy

The 5 pin plug is what connects the mirror housing to the back of the mirror. It is located on the back of the mirror itself and is between the motor drive and the body. There are other wires that connect to the motor that moves the mirror. The mirror glass doesn't always heat. There is a temperature sensor that is supposed to turn on the heating element when it is below freezing.

eddieo45

Thanks Jim, but it should be hot...it's 16 degrees in Massachusetts, and the passenger side is hot. So, not to be thick, but if the 5 pin is connected, and the mirror moves, what's NOT connected?

JimPurdy

The only suggestions would be to unplug the 5 pin connector and meter the pins. This is the oval 5 pin connector inside the mirror. Or the 2 pin connector between the door and the mirror. the pink wires (pink/red and pink/black) appear to be the ones connected to the heating element. There should be 12 V. on the car side of this circuit. If there isn't 12 V., I would check the fuse for this circuit. If there is 12 V. present, the thermostat could be defective. The thermostat appears to be in a rectangular bubble on the back of the mirror. If the mirror isn't very cold, the resistance is high (> 10 k-ohms) and very low when cold . You would have to freeze the mirror to check the difference in resistance to see if that is the problem. I wish I could be more help by checking the circuits in the car but I traded the W202 several months ago for a W211. I still have the repaired mirror so I can only check it. I have tried to sell the mirror assembly but they don't break that often.