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1987 420 SEL
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Discussion Starter · #1 ·
I searched for help on this topic before I posted. Couldn't find anything this specific. (and I hope this is the right part of the forum for this post).

I have a 1987 420 SEL. I noticed the driver's side headlight, was not working sometimes. Then other times it was. So I pulled it out, and the attached photo shows what I found. It has a definite burn/melted area on the "socket" or whatever the female part is called.

I checked the rest of the car and found I had bad weatherstripping in the trunk, and there was some water getting into the rear, driver's side tail light and break light housing area. I have since fixed the weatherstripping, and dried out the rear light housing and made sure it is all dry and clean; contacts are good.

could this be what caused my front headlight to do this? I know wiring and electrical issues can be very odd/gremlins etc..

Regardless, it looks like I need to replace the front headlight wiring. Is this difficult for a pretty good do-it-your-selfer like me?

Do I have bigger problems on my hands?

thanks for any advice!

JM
Atlanta, GA
 

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Always Remembered RIP
2015 ML 400 x 2
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16,613 Posts
very unlikely that rear problems are associated with your headlight.

Something has shorted out your headlight connector - correcting that is necessary, but a good DIYer can replace the connector easily.
 

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1987 420 SEL
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28 Posts
Discussion Starter · #3 ·
someone has suggested that I might be using too high wattage bulbs.... they are the same bulbs that have been on the car since I bought it 2 years ago.

They have blue tips on them..... what does that mean? thanks in advance!

sorry for replying to my own post!
:D
 

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1987 420 SEL
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Discussion Starter · #5 · (Edited)
I'll post one as soon as I get home in the next few hours...if you don't mind checking back!

(as far as the trunk leak..I have fixed that entirely....the weather stripping is fine now... no moisture in the brake light housing area.)

thanks!
 

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1982 500SL AMG "Darmstadt Branch"
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1,100 Posts
Those are the Xenon HID replacements I think...like on Ebay. I don't trust them.
 

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1987 420SEL
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If they are infact flea-bay HID's, throw them out and replace them with either the stock sealed beams or jump on the Euro wagon.

The most likely cause for your melted connectors is the fact that the lights don't match in terms of wattage. Your theory in post #3 makes sense.

You might want to clean your grounding straps with emery cloth as well, while you're in there, to ensure proper contact.
 

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1987 420 SEL
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Discussion Starter · #8 ·
Ok.

I was wrong...tips are not blue. duh.

They are, in fact, just like Huntrtylr posted. (see photo) they say 3A HDI or something like that (see photo) but both of them are the same (left and right)...could this still be the source of the problem?

I'm all for higher quality lights.... but I still want to be sure of the source of the melted connector. thanks. everyone on here is such a great help!

:bowdown:
 

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'73 450SL, '83 300CD, '01 E320 4matic
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If they are way high wattage, like 100 watts, it's possible that increased current consumption enough to make the kind of heat needed to melt that.

The problem actually is caused by a bad connection. Burned electrical connections in cars are 99% of the time caused by a poor connection somewhere. We had a run of bad headlight sockets at work that ran the same bulb as the US spec 126 that all looked just like that one.

When the connection is poor, a voltage drop occurs causing the current to increase. That = heat. The socket needs to be replaced at this point.

Check all connections, especially grounds. Any place that can cause a voltage drop in the circuit can cause this problem.

Even check the fuses. I don't remember on the 126, but it's possible that there are separate fuses for the headlights. I know there are on the 123.

Or upgrade to euros and control everything with relays :)
 

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1982 380SE AMG euro(parted out),1983 300SD "Good Girl", 1984 500SEL AMG euro "Bad Girl"
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If they are way high wattage, like 100 watts, it's possible that increased current consumption enough to make the kind of heat needed to melt that.

The problem actually is caused by a bad connection. Burned electrical connections in cars are 99% of the time caused by a poor connection somewhere. We had a run of bad headlight sockets at work that ran the same bulb as the US spec 126 that all looked just like that one.

When the connection is poor, a voltage drop occurs causing the current to increase. That = heat. The socket needs to be replaced at this point.

Check all connections, especially grounds. Any place that can cause a voltage drop in the circuit can cause this problem.

Even check the fuses. I don't remember on the 126, but it's possible that there are separate fuses for the headlights. I know there are on the 123.

Or upgrade to euros and control everything with relays :)
Not to bust your chops akimball442 but you've almost got it spot on. When you have a poor connection you have added resistance and get a voltage drop. A clean connection is in the milliohm range but when a poor connection comes into play, resistance really goes up. The device behind the connection is designed to allow x amount of current through and the circuit will still try to let that amount through, but now that current is also flowing across a voltage drop. That voltage drop, multiplied by the amount of current flowing through it, is refered to as...power, measured in watts being generated in your circuit where the added resistance is. Current in the circuit is almost the same but the power is being used where it shouldn't like melting stuff. Good point on checking grounds and fuses out. A poor connection on the fuse will cause it to melt due to heat. The circuit also needs a clean path to ground to do it's job. :thumbsup:
 

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1982 500SL AMG "Darmstadt Branch"
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Do you know if there is a DIY HID ballast Kit installed? If so these are famous to burn and that is deff. the source. These powered bulb coated halogen 100w bulbs that will not only melt your headlight housing but entire wiring harness. These bulbs from the company's like Raybrig, Polarg, Catz and Piaa sell these bulbs that produce a tremendous amount of heat to produce less light than a plasma and xenon filled bulb that is included in an HID kit.
 

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1987 420 SEL
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28 Posts
Discussion Starter · #12 ·
Thanks to all of you for the great info.... while much of it is over my head, I still love reading it and trying to learn something. (electrical is tough for me)

Huntrtylr, how would I know if there was a DIY HID kit installed? Not sure what to look for. This car was literally a "little old lady's" Benz.... so I am not sure there is anything custom about it. One reason I like it so much! :)

But maybe I am not understanding.... regardless.... I think I will have to let my mechanic help me out here... I talked to him and he says, with a German accent: "let me look, perhaps I can find a connector and we can use some wire connectors to plug it to the wiring harness."

sigh

:confused:
 

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1982 500SL AMG "Darmstadt Branch"
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You will have something that looks similar to this. Each side has a box taped down or mounted some place near the light. Follow the wire should not be be more than 2-3ft.
 

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'73 450SL, '83 300CD, '01 E320 4matic
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Do you know if there is a DIY HID ballast Kit installed? If so these are famous to burn and that is deff. the source. These powered bulb coated halogen 100w bulbs that will not only melt your headlight housing but entire wiring harness. These bulbs from the company's like Raybrig, Polarg, Catz and Piaa sell these bulbs that produce a tremendous amount of heat to produce less light than a plasma and xenon filled bulb that is included in an HID kit.

The bulb he's holding in his hand in the pic is a standard halogen headlight bulb.
 

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1987 420 SEL
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Discussion Starter · #15 ·
Yeah, I could not find anything that looks like that kit....

So it looks like there's a bad connection somewhere.... and old wire etc?

I tried to trace the origin of the cable/wire/connector...briefly.... and did not get very far! I will try again when i have some time.

I don't have any equipment to test this stuff (volt meters or whatever I need)... and I know little about electronics.... I am a pretty good DIYer though.... hmmmm....thanks everybody
 

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'73 450SL, '83 300CD, '01 E320 4matic
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Automotive electronics is my job :)

I don't think you have anything major going on there. I'd replace the socket, and then install some new headlights (both sides, so they match). You'll probably be just fine.

Chances are there is just a loose terminal in the bulb socket causing an intermittent connection. If it was something serious like a short, you'd have blown fuses, not an intermittent fault.

You could probably just grab a replacement at a junkyard.
 
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