Passenger headlight only works when the car is OFF. Flickers and fails when car is on
Thread Starter
Member
Joined: Mar 2013
Posts: 200
Likes: 2
2007 c280
Passenger headlight only works when the car is OFF. Flickers and fails when car is on
I've never seen anything like this before. For a couple weeks my passenger side low beam has been flickering and turning off. Ordered new bulbs and installed them last night. While installing them I turned them on with the car off and they worked just fine. Later in the evening I go to take a drive and upon starting, the same headlight flickers and turns off when the car is on and I turn on the low beams. If i turn off the headlight, and turn them back on the same thing happens, turns on, flickers, and dies in 5 seconds.
So I turn the car off, turn the headlights ON and both work fine for as long as the car is not started. With the headlights on as I start the car both beams will remain on for about 30 seconds. Then the passenger low beam flickers and dies again.
Im clueless here. To me, its a relay issue or the headlight switch itself.
Any ideas here guys?
2007 C280 4MATIC
Thanks!
So I turn the car off, turn the headlights ON and both work fine for as long as the car is not started. With the headlights on as I start the car both beams will remain on for about 30 seconds. Then the passenger low beam flickers and dies again.
Im clueless here. To me, its a relay issue or the headlight switch itself.
Any ideas here guys?
2007 C280 4MATIC
Thanks!
Last edited by Stuka Bomber; Nov 7, 2018 at 08:36 AM.
Super Member
Joined: Apr 2004
Posts: 783
Likes: 108
From: PA
E Coupe C207, ML W166, ML W164, Sprinter 1500/144, W111 SB220 Fintail(s), A5 chassis Beetle 5+5
Inspect the wiring inside the headlamp housing. It's biodegradable wiring harness, and decays rapidly, allowing for shorts. Mine are bad, but don't short atm. I'm considering using some liquid electrical tape on them, but might get new ones.
Newbie
Joined: Nov 2018
Posts: 8
Likes: 0
C230 K
Ground issue. Follow the wiring along the fenders and find the common ground. Should be a 10mm nut, you'll likely find it loose. If so tighten and it'll probably fix your issue. The car running is vibrating enough to make the difference in a good connection and not. If that doesn't work, I'd do as Audi Junkie said and make sure the wires in and outside the housing are not shorting by touching bare wires. The wiring has always been horrible in these areas. The rubber disintegrates leaving bare wires to short and cause all kinds of gremlins.
Junior Member
Joined: Feb 2007
Posts: 49
Likes: 0
From: 3rd rock from the sun
C230 SC 2002 White 1992 Toyota Hilux 225,000 miles, 2017 Subaru STI
The wiring insulation in both my headlights has disintegrated. It’s unbelievable how brittle these cars have become. My 30 year old Toyota is pristine with little upkeep. Sorry, but wire insulation should not just disappear into fairy dust. Damn fire hazard.
MBWorld Fanatic!
Joined: Dec 2003
Posts: 3,275
Likes: 236
From: BC, Canada
2003 C230K Coupe Orion Blue
Just curious, did anything happen to the wiring beforehand?
The stuff in my headlights is still basically brand new.
So is all the harness wiring, despite being splattered with oil and other fluids over the years.
The stuff in my headlights is still basically brand new.
So is all the harness wiring, despite being splattered with oil and other fluids over the years.
Junior Member
Joined: Feb 2007
Posts: 49
Likes: 0
From: 3rd rock from the sun
C230 SC 2002 White 1992 Toyota Hilux 225,000 miles, 2017 Subaru STI
No. Car has been mostly garage kept since I got it. The plastics and rubber have turned into sand. The wiring insulation is now perished. Might be a for sale sign on it soon. About 88000 miles. Mechanicals are not problematic. 6 speed manual.
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Member
Joined: May 2021
Posts: 121
Likes: 22
From: Melbourne, Vic, Australia
C230K M271 CL203 2003 model
Hi GrandPrix, Do you live in an extreme climate area? Freezing or very high temps?..
my wiring looks solid for now, but i maybe lucky to live in a moderate climate area, with mild winters, and not too hot summers..?
my wiring looks solid for now, but i maybe lucky to live in a moderate climate area, with mild winters, and not too hot summers..?
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