Glk 350 auxiliary battery dead, I知 so happy!
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2013 glk 350
Glk 350 auxiliary battery dead, I知 so happy!
My glk 350 auxiliary battery failed, I知 so happy it won稚 operate Stop Start now. Is there any other purpose for this battery other than the annoying Stop Start? I like not having to deal with turning off Stop Start.
Senior Member
Joined: Jul 2014
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From: South East US.
2015 GLK350
Interesting. On my 2015 the start/stop quit working when my main battery got low and started working normally only after I replaced the main battery. At first I thought it was the AUX battery getting low so I replaced that one first without any noticeable effect.
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Joined: Aug 2015
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From: Washington State
2013 GLK 350 4Matic
Depending on what caused the Aux battery to fail, it could start pulling your main battery down. If the switching relay failed and didn't charge your Aux battery, your probably OK, but if the relay keeps trying to connect the aux to the main, as it does normally, it could end up being a drain on the main battery. The relay usually waits til the car is running for a given period and then, if the main voltage tests OK, it will try to switch the two batteries together and charge them at the same time.
The only load I know for sure on the Aux battery is the electric transmission fluid pump that keeps the pressure up when the car stops under ECO. If ECO isn't working then I don't think the pump is used. I wouldn't be surprised if there are more loads on that battery, but haven't found any documentation on them.
I don't like the ECO function, but after all this time, I just automatically switch it off every time I start.
The only load I know for sure on the Aux battery is the electric transmission fluid pump that keeps the pressure up when the car stops under ECO. If ECO isn't working then I don't think the pump is used. I wouldn't be surprised if there are more loads on that battery, but haven't found any documentation on them.
I don't like the ECO function, but after all this time, I just automatically switch it off every time I start.
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Joined: Feb 2022
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GLK 350 4Matic
Auxiliary battery dead.
Hi All. I just. bought my GLK 350 3 months ago, and I am starting to know better this car in this Forum. I am a new MB user.
The start/stop has never worked since I bought the car. The auxiliary battery might be dead. The main battery shows around 14 volts reading on the dash.
I have talked with a specialized MB mechanic about it. He told me that I should only replace the batteries using the original MB ones.
Are there any other reliable aftermarket brands?
What do you guys think about that?
The start/stop has never worked since I bought the car. The auxiliary battery might be dead. The main battery shows around 14 volts reading on the dash.
I have talked with a specialized MB mechanic about it. He told me that I should only replace the batteries using the original MB ones.
Are there any other reliable aftermarket brands?
What do you guys think about that?
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2013 glk 350
Any quality AGM battery will work fine if it痴 the same or larger capacity. If your auto stop start doesn稚 work don稚 replace the small secondary battery. Stop start is not only annoying , it痴 hard on the starter and let痴 the oil drain out of the motor , your lucky it doesn稚 work.
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GLK 350 4Matic
Any quality AGM battery will work fine if it痴 the same or larger capacity. If your auto stop start doesn稚 work don稚 replace the small secondary battery. Stop start is not only annoying , it痴 hard on the starter and let痴 the oil drain out of the motor , your lucky it doesn稚 work.
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I think the M-B aux. battery has had different functions or "responsibilities" over the years and also depending on the M-B model.
One thing I have read is that it is also there to allow the electronic shift mechanism to work in the event of a main battery failure. Makes sense to me as you may have the need to put the vehicle into either neutral or Park based on your situation if/when the main battery fails.
For a long time I planned to modify my aux. battery setup (don't like/want/use ECO start/stop) to directly run one of those large plastic camping coolers that run off of 12 volts. The idea being I could run the cooler for extended periods even with the engine off and not be concerned about my car not starting because I discharged the main battery.
One thing I have read is that it is also there to allow the electronic shift mechanism to work in the event of a main battery failure. Makes sense to me as you may have the need to put the vehicle into either neutral or Park based on your situation if/when the main battery fails.
For a long time I planned to modify my aux. battery setup (don't like/want/use ECO start/stop) to directly run one of those large plastic camping coolers that run off of 12 volts. The idea being I could run the cooler for extended periods even with the engine off and not be concerned about my car not starting because I discharged the main battery.
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If it fails while driving, at some point you will stop and shut off the engine. It may go into Park when you shut down but you may want it in neutral. If it doesn't go into Park you may want to put it in Park after the engine is shut off.
It's all about Murphy's Law and having options - assuming that what I read is accurate (that a good Aux. batt. will allow the shifter to work).
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2013 glk 350
I find the headache of having auto stop start very annoying . The last thing I will do is keep a weak main battery. But yes many don稚 maintain their main batteries. Auto stop start should have been made able to be turned off
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'17 GLS450, '14 GLK250, Grandpa's Roadster
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Modern car batteries don't require maintenance. Bluetec models never had auto stop/start. I wish mine had start/stop now that diesel is well over $6/gallon.
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2015 E400 and 2015 GLK350
The Aux battery also powers the "HOLD" function -- where an extra press on the brake pedal when stopped will hold the brakes without any pedal pressure until you press the accelerator again to pull away.
No Aux battery, no HOLD function.
No Aux battery, no HOLD function.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
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Tested my GLK today.
Disconnected my main battery - simulating a completely dead main battery. Aux. battery did NOT power the electric parking brake/shift function or hold function. Could not engage or disengage the electric parking brake. No brake hold functionality. Aux. battery did nothing.
Vehicle:
2014 GLK 350 4Matic with Keyless Go and Eco Stop/Start. U.S. specs.
Disconnected my main battery - simulating a completely dead main battery. Aux. battery did NOT power the electric parking brake/shift function or hold function. Could not engage or disengage the electric parking brake. No brake hold functionality. Aux. battery did nothing.
Vehicle:
2014 GLK 350 4Matic with Keyless Go and Eco Stop/Start. U.S. specs.
I think the M-B aux. battery has had different functions or "responsibilities" over the years and also depending on the M-B model.
One thing I have read is that it is also there to allow the electronic shift mechanism to work in the event of a main battery failure. Makes sense to me as you may have the need to put the vehicle into either neutral or Park based on your situation if/when the main battery fails.
For a long time I planned to modify my aux. battery setup (don't like/want/use ECO start/stop) to directly run one of those large plastic camping coolers that run off of 12 volts. The idea being I could run the cooler for extended periods even with the engine off and not be concerned about my car not starting because I discharged the main battery.
One thing I have read is that it is also there to allow the electronic shift mechanism to work in the event of a main battery failure. Makes sense to me as you may have the need to put the vehicle into either neutral or Park based on your situation if/when the main battery fails.
For a long time I planned to modify my aux. battery setup (don't like/want/use ECO start/stop) to directly run one of those large plastic camping coolers that run off of 12 volts. The idea being I could run the cooler for extended periods even with the engine off and not be concerned about my car not starting because I discharged the main battery.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Disclaimer: I have no knowledge on this subject!
Could it be that it will only take over if the car is running? If the car is off, then there's no "emergency".
Could it be that it will only take over if the car is running? If the car is off, then there's no "emergency".
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I don't think so but, in any event, I would like to be able engage or disengage the electric parking brake with a dead main battery. Guess a "jump" would be necessary.
I wouldn't disconnect the main battery while the car is running, to test. Could lead to ugly things.
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S204 C250 CDI Sport
Update...
This isn't so on my facelift S204 but appreciate not all Mercedes models are same .
Eco Stop Strain will not save you money nor save the planet but is a clever marketing piece of machinery that does exactly the opposite....
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2017 GLE350 4MATIC
...and reduces the longevity of the starter.
