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Q: Head lamp stays on

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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.

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