'Auxiliary battery malfunction' on startup - 2014 CLS63S
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From: Scottsdale, Arizona
2020 S63 Coupe, 2006 Hummer H1 Alpha, 2018 McLaren 720S, 2022 Porsche 911 TurboS, 2022 Tesla Model X
'Auxiliary battery malfunction' on startup - 2014 CLS63S
Had the main (engine compartment) battery die recently, it was replaced by roadside. It failed spectacularly overnight, car wouldn't start and was giving me less than 10v when I hooked up a charger.
Now I'm getting a 'auxiliary battery malfunction' error sometimes, not always, when I start the car, a 2014 CLS63 S. I've checked the trunk battery (for ECO, I think) and it reads 12.9-13v with the car off and disconnected, so isn't dead and is getting charged.
So does the CLS63 have a third 'auxiliary' battery - maybe the small transmission backup battery like some of the E-Class models have ? I know it is hidden below the dash on those, but thought it was only used in cars with the steering column shifter stalk. The CLS63 obviously has a console shifter, although it is really just an toggle lever so functionally is probably similar to the stalk shifter.
I'm sure the dealer would fix it under warranty if I bought it in, but if it just needs a cheap 12v lead acid battery with standard connectors, I'd just buy one and install myself. But I don't want to take a bunch of panels off, if it isn't in there...
Now I'm getting a 'auxiliary battery malfunction' error sometimes, not always, when I start the car, a 2014 CLS63 S. I've checked the trunk battery (for ECO, I think) and it reads 12.9-13v with the car off and disconnected, so isn't dead and is getting charged.
So does the CLS63 have a third 'auxiliary' battery - maybe the small transmission backup battery like some of the E-Class models have ? I know it is hidden below the dash on those, but thought it was only used in cars with the steering column shifter stalk. The CLS63 obviously has a console shifter, although it is really just an toggle lever so functionally is probably similar to the stalk shifter.
I'm sure the dealer would fix it under warranty if I bought it in, but if it just needs a cheap 12v lead acid battery with standard connectors, I'd just buy one and install myself. But I don't want to take a bunch of panels off, if it isn't in there...
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From: NYC
'01 S500 AMG Sport, ABC,Distronic,Rear Side Shades // '10 E350 P2, Pano, BLK/ALM,4MATIC Sport
Originally Posted by Heisenberg
Had the main (engine compartment) battery die recently, it was replaced by roadside. It failed spectacularly overnight, car wouldn't start and was giving me less than 10v when I hooked up a charger.
Now I'm getting a 'auxiliary battery malfunction' error sometimes, not always, when I start the car, a 2014 CLS63 S. I've checked the trunk battery (for ECO, I think) and it reads 12.9-13v with the car off and disconnected, so isn't dead and is getting charged.
So does the CLS63 have a third 'auxiliary' battery - maybe the small transmission backup battery like some of the E-Class models have ? I know it is hidden below the dash on those, but thought it was only used in cars with the steering column shifter stalk. The CLS63 obviously has a console shifter, although it is really just an toggle lever so functionally is probably similar to the stalk shifter.
I'm sure the dealer would fix it under warranty if I bought it in, but if it just needs a cheap 12v lead acid battery with standard connectors, I'd just buy one and install myself. But I don't want to take a bunch of panels off, if it isn't in there...
Now I'm getting a 'auxiliary battery malfunction' error sometimes, not always, when I start the car, a 2014 CLS63 S. I've checked the trunk battery (for ECO, I think) and it reads 12.9-13v with the car off and disconnected, so isn't dead and is getting charged.
So does the CLS63 have a third 'auxiliary' battery - maybe the small transmission backup battery like some of the E-Class models have ? I know it is hidden below the dash on those, but thought it was only used in cars with the steering column shifter stalk. The CLS63 obviously has a console shifter, although it is really just an toggle lever so functionally is probably similar to the stalk shifter.
I'm sure the dealer would fix it under warranty if I bought it in, but if it just needs a cheap 12v lead acid battery with standard connectors, I'd just buy one and install myself. But I don't want to take a bunch of panels off, if it isn't in there...
MBWorld Fanatic!
Joined: Dec 2013
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E63
As far as I am aware we only have two batteries, main one under the AC air inlet under the hood and second accessory one in the truck.
I just changed both of mine recently and those were the only two batteries MB gave me options for
I just changed both of mine recently and those were the only two batteries MB gave me options for
