Skip the auto shop - Our mechanics make house calls

Q: Head lamp stays on

asked by on

My Mercedes's right headlamp stays on all the time and drains my battery. The dealer can figure out what is wrong. The low voltage causes the radio not to work. This is so frustrating. Can you think of any way to fix it? I am tired going to the dealer. Thank you.

Hey there, thanks for writing in about your 2010 Mercedes-Benz R350. Have the control module under the driver’s seat checked to see if any water was introduced and has gotten it wet. If it has, then the A/C drain hoses for the evaporator drain are clogged or blocked in some way and the water is getting the module wet resulting in different problems with the lights and radio. For this situation, I recommend having a qualified professional, such as one from YourMechanic, inspect your battery draining issue first in order to get the electronics of your car working again.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Is there another way to remove crank sensor

Working with damaged bolts is one of the things that can really challenge even the most experienced mechanic. The fastener has to come out to change the part, and if the head is distorted, you're going to have to use...

Q: Heat in car is not hot

This may suggest the thermostat might be stuck open or you may have a clogged heater core. As you know, if the thermostat is stuck open, the coolant circulates constantly never allowing the motor to fully warm up and therefore...

Q: Why my infotainment automatically turns off every 10 minutes even while driving?

I believe this issue would be related to the control unit itself or your settings inside the unit. Although unlikely, it is possible that there is a setting that makes the radio turn off at specified intervals that you can...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...