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Hello community! I own a 2014 e350 4Matic, and its given us solid service for a little while. 88K on the car, but after sitting for a few weeks while I left the state, the passenger side headlamp assembly is acting up. I just swapped in a new headlight assembly and much to my misfortune, I have the same dilemma. Low beam is dead, DRL is dead, and the three little yellow LEDs on the low beam cowl are dead.
I'm chasing wires at this point
Please send help
Updates, im following wiring diagrams, testing for power and such at the connectors.
Referring to the left headlamp connector, Black/red wire has battery voltage, which im assuming powers the low, DRL, and 3 leds.
Right headlamp has no power at the Red wire.
I wired together the Black/red and Red, blew fuse 74 in the rear compartment.
Fuse 89 was blown, and upon replacing it, blew within 2 seconds.
I assume there is some ****ery going on with the Red wire thats supposed to have constant live power.
My next step is splicing in live power from the battery to the headlamp assembly.
Messing around, will update.
Lmao in my frustration, standing around smoking a cigarette, I AM cleaning the bugs off while i ponder this dilemma. I might have to trace this Red wire from the headlight to the rear fuse box..
Haha I hear ya, unfortunately you have to be a NASA scientist to read WIS wiring diagrams. Such a nightmare. I can post them if you want though. Otherwise, what are you referencing for info? Or do you already have WIS
Updates, im following wiring diagrams, testing for power and such at the connectors.
Referring to the left headlamp connector, Black/red wire has battery voltage, which im assuming powers the low, DRL, and 3 leds.
Right headlamp has no power at the Red wire.
I wired together the Black/red and Red, blew fuse 74 in the rear compartment.
Fuse 89 was blown, and upon replacing it, blew within 2 seconds.
I assume there is some ****ery going on with the Red wire thats supposed to have constant live power.
My next step is splicing in live power from the battery to the headlamp assembly.
Messing around, will update.
If direct power from battery helps then you could take power directly from battery thru a simple relay and use the driver side light red wire voltage to trigger the relay.
I'd suggest getting a copy of EPC/WIS of eBay to gain access to factory wiring diagrams... not sure why your splicing various wires together. If a fuse is blowing instantly you have a bigger problem. So none of the lights (low/hi beam, turn, parking, DRL) function on the right side?
Provide your VIN, in the mean time we can provide the appropriate wiring diagrams. Do you have a capable scanner? Another issue, is these are not simple switched 12V circuits...
I have purchased the factory wiring diagrams from https://portal-diagnostov.com/en/202...ring-diagrams/ and have been using them to follow the wiring and its pretty retarded.
The Red behind the headlamp on that diagram just goes to fuse 74 in the trunk, but i blew fuse 74 when i jumped the Black/Red from the drivers headlight to the passenger headlight.
I had a heart attack and thought I messed up the other side. But that was remedied by a 20amp fuse. No change in passenger lamp function. I was considering installing a relay. Thank you.
Fuse 89 is perplexing, but I will be doing a continuity test on that Red wire, that slipped my mind. WDDHF8JB7EB000952, passenger side high beam and the yellow blink when I hit lock functions properly. I thought the headlamp circuitry malfunctioned so I purchased a new headlight that broke my heart.
10-08-2021, 11:54 PM
