Bad battery c350
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Junior Member
Joined: Mar 2023
Posts: 43
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W204 c350 coupe, w218 cls63s
Bad battery c350
I got a 13 c350 coupe and the main battery keeps dying when I keep the door open too long or play music with the car off, it has been diagnosed as a bad battery. My mechanic said that both batteries need to be replaced even though the one in the trunk is still good. I trust him since he is certified Mercedes tech but just would like to know if that’s the case since $950 cad for two batteries is a lot of money
MBWorld Fanatic!
Joined: Oct 2019
Posts: 5,156
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From: Colorado
G550
If you've been keeping your car going by charging/jumping the main battery, start with replacing it. If you're a DIY'er, you can get a new starter battery at Canadian Tire for around $300 CAD, depending on what size and warranty you need. Here in the U.S. some of the auto stores will even do the install for you.
Out Of Control!!
Joined: Apr 2019
Posts: 11,990
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
battery woes
I got a 13 c350 coupe and the main battery keeps dying when I keep the door open too long or play music with the car off, it has been diagnosed as a bad battery. My mechanic said that both batteries need to be replaced even though the one in the trunk is still good.
I trust him since he is certified Mercedes tech but just would like to know if that’s the case since $950 cad for two batteries is a lot of money
I trust him since he is certified Mercedes tech but just would like to know if that’s the case since $950 cad for two batteries is a lot of money
The smaller AUX battery gets drained automatically when the chassis voltage gets low, it supplies essential modules with power.
Draining batteries expedites them getting low then eventually getting limited capacity.
Last edited by CaliBenzDriver; Jun 1, 2024 at 12:58 PM.
Super Member
Joined: May 2024
Posts: 506
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From: Northern Indiana
2014 c300 w204.080 3.5 v6
You can buy batteries in rock auto. When I did mine I used the ac Delco Agm style batteries for my car and they have been great. Paid like $275 and I ate the small core return and took my battery to the scrap yard for some cash. Very simple to swap out the battery's with dinner basic hands tools
Last edited by RobertR728; Jun 1, 2024 at 02:26 PM.
