Louisgcl

Auxiliary Battery Malfunction

11 posts in this topic

My ride: C200 Sport (PI) Latest model

Hi C- Class owners, I having problem in my ride, It keep showing auxiliary battery malfunction even i press ok. Kindly advice whether does C200 have any backup battery? Please advice any workshop that is specialist in this. Thanks 

 

Appreciate your advice.

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Sometimes, vehicle park too long didn't use (example: parking at yard pending inspection, waiting for buyer) will result battery malfunction. Our sponsors MBM or optima etc should be capable doing this simple work

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The auxiliary battery is the one in the front. Normal battery life span between 14 to 18 months. Tell tale sign of battery failing: sudden dim of lights, double cranking on start, jerky ride.

Change of battery, as soon as signs appeared is always better than having to tow car to WS or wait for AA truck to come by (waste of time). Save lots of agony.:hot:

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Bros....u are barking on the wrong tree. Aux batt is NOT the main batt found under the hood. It's a small 12V batt used for the Eco start/stop feature. It's found behind the glove compartment of a CLA or A class. Not sure where it's found in W205...I believe it's somewhere there too. Even though the warning sign shows a fault in aux batt, the car can still start up & move normally as that relies on the main batt. 

Who can fix this? Better go back to C&C...

 

looks something like this...

 

image.jpeg

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Bro, the main battery is usually located in the boots while the one under the hoot is the auxiliary battery. At least that's what I learnt from C&C WS and, I think, it is also mentioned in the owner's manual..:hot:

Previously I thought that whatever under the hoot (in the main engine compartment) is obviously the main battery...:lol:

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For W205... The main batt is under the hood in the front lah.

 

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Certain cars have 2 battery, 1 in front and 1 in boot. In that case, front is starter battery and boot is main battery to power all your barang barang. 

Some battery in the boot is located in a hidden compartment behind the rear seats (like the s class). it's not placed next to the spare tyres. So u may want to be sure if there is a boot battery.

If your car only 1 battery , it powers everything including starter, just like jap car.

Aux battery is a small battery under side dashboard. To power your ecu. Usually it can last a long long long time

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Need help ! Can anyone advise where I got get the auxiliary battery for W205? 

I need to replace it . Thank you in advance 

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I went to PAS Auto the MD parts supplier. They said is not a real battery. Just a voltage converter. 

I struggled to locate it. Anyone know where is the location? 

D8D6BF0F-4C4C-4F90-90F9-3978A0FAD519.jpeg

7EFE80D8-3F4A-4001-ACD8-8FCA579AE6E2.jpeg

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Finally got it done. The ‘Auxiliary battery’ which is actually a voltage converter unit and located infront of the passenger floor. After changing you need to do a reset. Cannot DIY. 

 

878EB568-6123-445F-A13C-C4825290FB8E.jpeg

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Hi Angchug, 

Did u face this problem, everytime the car restarts after start-stop mode, the radio restarts itself.. 

Changed the main battery but problem still persist. 

Should i change the auxiliary battery? 

How much did yours cost and the workshop u went to? 


Thank you very much 

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