Mercedes GLC 220d 2015 - Secondary Battery

Tony Mac said:

The Auxiliary Battery is not a physical battery - it’s a Large Capacitor that provides energy for the Stop / Start function.

This Capacitor is located under the passenger side footwell - there’s a excellent thread on the Forum by Toobad that explains how to change this component.

I was seeing the same Warning message and someone suggested checking Fuse 448 - in the floor of the boot.

After simply removing and reinserting the same fuse 448 - the Warning stopped for me and has not appeared since - amazing and definitely worth trying

Good luck

Click to expand...

Tony Mac said:

The Auxiliary Battery is not a physical battery - it’s a Large Capacitor that provides energy for the Stop / Start function.

This Capacitor is located under the passenger side footwell - there’s a excellent thread on the Forum by Toobad that explains how to change this component.

I was seeing the same Warning message and someone suggested checking Fuse 448 - in the floor of the boot.

After simply removing and reinserting the same fuse 448 - the Warning stopped for me and has not appeared since - amazing and definitely worth trying

Good luck

Click to expand...

Philipeo121 said:

Thanks Tony huge help will try that

Click to expand...

Tony Mac said:

This is the thread

Auxiliary Battery Malfunction

So, 8 weeks after the 3-year warranty expired, Red Ken decided to invoke the Law of Sod and throw up a "Auxiliary Battery Malfunction" warning. Ever the Drama Queen, he decided to flash this warning up on the dash in red letters and accompany it with a repeated warning sound to fully focus my...

www.glcforums.com

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