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Low beams keep burning out

6K views 14 replies 9 participants last post by  pounce 
#1 ·
I found several posts mentioning this problem but no one seemed to have a solution. I have a 2019 Metris used as a livery vehicle. It has 70,000 miles and I have installed 6 low beam bulbs. It seems like the original bulbs lasted to around 50,000 miles, but I need to search my maintenance records to confirm this. I think the left side is on its 3rd bulb, and the right is on its 5th. To contrast this, I have owned five 2016 E350 sedans racking up over 700,000 miles total and changed a total of one H7 bulb.

  1. What is the problem here?
  2. Anyone know the part number for the fender access covers?
 
#2 ·
I haven't seen root cause nor a solution. In some 90K miles, I've replaced the right low beam four times. The left has not failed. Yet.

A month or so ago, I replaced both sides with these: Amazon.com: YGINNO H7 LED Headlight Bulbs with Specific Adapter Retainer for Volkswagen VW Golf GTI, Super Bright 8000 Lumens All-in-One H7 LED Headlights Conversion Kits, 6500K Cool White, Pack of 2 : Automotive

I was surprised when I put these in to notice that the little fender cover was missing on the driver's side :-(
 
#5 ·
I haven't seen root cause nor a solution. In some 90K miles, I've replaced the right low beam four times. The left has not failed. Yet.

A month or so ago, I replaced both sides with these: Amazon.com: YGINNO H7 LED Headlight Bulbs with Specific Adapter Retainer for Volkswagen VW Golf GTI, Super Bright 8000 Lumens All-in-One H7 LED Headlights Conversion Kits, 6500K Cool White, Pack of 2 : Automotive

I was surprised when I put these in to notice that the little fender cover was missing on the driver's side :-(
I got the same ones and the left burned out the 30th day the last day before the return expired. I could have my money back but got the replacement because I got them last holidays sale for just $39 after the coupon on page. The beams are not quite good I lower the head lights down so they don't blind other drivers. Before I got these LED I bought the Phillip halogen bulbs 200x Racing ones more expensive but no where near this brightness.

Today I have an email with similar LED H7 for $48.99 Plus 8% coupon on Amazon product page (just like no paying sales tax) and thinking about trying them.

 
#3 ·
Nothing concrete but...

Be sure you do not touch with your bare hands any part of the new bulbs. Use clean mechanics gloves or in a pinch I have used a small sandwich baggie to handle light bulbs.

You can use a piece of fine sand paper to just rough up the contact points to remove any corrosion. But just a wipe or two. Remove too much metal and the contacts can become compromised.

Be sure the bulb is in the socket securely. This can be tricky. With another vehicle -- long story short -- I found when installing a new turn signal bulb in the headlight assembly the bulb felt secure but electrical contact was not good.

I had to resort to using an ohm meter to confirm the bulb was making good contact in its socket. This required "fiddling" to accomplish this. Socket not damaged and showed no signs of anything amiss. Was not possible to bend anything to improve the connection. Even using the ohm meter to confirm a good connection about once or twice a year I had to reseat the bulb. It would work loose when I had the car parked in direct sun on a really hot day. The other headlight assembly never exhibited any problems. But it was newer than the one that did. The cost of a new headlight assembly was prohibitive. Bi-Xenon headlights. Very good lights but oh my expensive.

I'd also check battery voltage at the battery with the engine idling in P and the lights off and then on on to confirm the voltage was within reasonable limits. A high of 14.5V with a low of 13.8V is about (about) the norm. The voltage may not change much. The range is about what the voltage should be pretty much regardless of any additional electrical loads. Check the voltage at the light bulb connector too. You want to look for excessive voltage (or even too low voltage.)

Last but not least be leery of using just any bulb. My SOP is to source bulbs at the dealer. Lower cost bulbs can be attractive but not if you have to replace them frequently...
 
#4 ·
Nothing concrete but...

Be sure you do not touch with your bare hands any part of the new bulbs. Use clean mechanics gloves or in a pinch I have used a small sandwich baggie to handle light bulbs.

You can use a piece of fine sand paper to just rough up the contact points to remove any corrosion. But just a wipe or two. Remove too much metal and the contacts can become compromised.

Be sure the bulb is in the socket securely. This can be tricky. With another vehicle -- long story short -- I found when installing a new turn signal bulb in the headlight assembly the bulb felt secure but electrical contact was not good.

I had to resort to using an ohm meter to confirm the bulb was making good contact in its socket. This required "fiddling" to accomplish this. Socket not damaged and showed no signs of anything amiss. Was not possible to bend anything to improve the connection. Even using the ohm meter to confirm a good connection about once or twice a year I had to reseat the bulb. It would work loose when I had the car parked in direct sun on a really hot day. The other headlight assembly never exhibited any problems. But it was newer than the one that did. The cost of a new headlight assembly was prohibitive. Bi-Xenon headlights. Very good lights but oh my expensive.

I'd also check battery voltage at the battery with the engine idling in P and the lights off and then on on to confirm the voltage was within reasonable limits. A high of 14.5V with a low of 13.8V is about (about) the norm. The voltage may not change much. The range is about what the voltage should be pretty much regardless of any additional electrical loads. Check the voltage at the light bulb connector too. You want to look for excessive voltage (or even too low voltage.)

Last but not least be leerank you for your detailed reply.y of using just any bulb. My SOP is to source bulbs at the dealer. Lower cost bulbs can be attractive but not if you have to replace them frequently...
Thank you for your detailed reply. You have the same approach that my mechanic is taking. I ordered new bulbs and they are insisting that I let them install them. I do use rubber gloves so I don't think that is the problem.
 
#9 ·
I had a same problem. I replaced the bulb 3 times in one year. I decided go with led bulb. I replaced with led but didn't like the brightness so I kept changing with different product. After 4 led bulb, I finally found a led bulb. They are white and very bright. Just like newer European car. It's been 2 years and still working strong. I will put pictures next time. You don't need to modify anything.
 
#11 ·
I was unable to find just the socket for sale by MB. I bought a whole light assembly. Took out the socket from the new assembly and stabbed it into the old housing. It snapped in and felt like a more precise fit. No problems anymore.

Prior to fixing the problem I discovered that the socket was loose and with light pressure towards the center of the van the bulb comes on. We drove about 500 miles with a clamp that I rigged and we did not have any more problems until the clamp failed!

My conclusion is it is the socket not the light housing. I will need some time to see if the bulbs are still burning prematurely.

Note: The "socket" discussed here is a male connection holding the bulb. I have always thought of a "light socket" as being a female connection. In this case the bulb socket snaps into the housing socket. Two sockets for one bulb.
 
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