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Lion Yard Trading
Mercedes-Benz · Ignition, Starting & Charging

Auxiliary / backup battery

A second, smaller battery supporting the electronics — stop-start restarts, or keeping modules alive while the main battery is under load.

Also called backup battery, consumer battery, secondary battery.

How you know it is this

  • Stop-start no longer working, with a message saying so
  • Odd electrical faults that come and go
  • A warning about the auxiliary battery specifically
  • The car behaving strangely for a moment at every restart

Worth knowing before you buy

  • Many owners do not know their car has one, and replace the main battery repeatedly while the auxiliary is the problem.
  • Small, and usually much cheaper than the main battery — but often hidden under a seat, in a wing or in the boot.
  • Stop-start refusing to work is the commonest sign and is usually put down to the system rather than a battery.

What we need to quote it. The chassis number. The chassis number settles the generation, the body and usually the engine in seventeen characters — it is on your mulkiya. A photograph of the old part helps where there is more than one version.

BatteryBattery sensor and terminalsEarth strapsStarter and solenoidAlternator and pulleyVoltage regulatorIgnition switch
Starting and charging — schematic, to show where the part sits. Arrangement is right; it is a diagram and not a fitment reference.

Rest of the starting and charging

All ignition, starting & charging parts
Get in touch

Auxiliary / backup battery for your Mercedes-Benz?

Send the chassis number and a photograph of the old part. We come back with genuine, OEM and aftermarket options priced side by side, with lead times.

Mon–Sat, 8:00 AM – 6:00 PM · +971 54 303 3119 (Operations Director) · +971 54 241 0599 (Managing Director)