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The auxiliary battery is a backup for the main battery. It does a number of jobs depending on what model of car it’s installed in. These range from powering electrical accessories like the radio/infotainment to operating the engine stop-start system.
Is it safe to drive with auxiliary battery malfunction?
Symptoms. When the main battery dies, the car won’t start. The car starts when the auxiliary battery dies, but an auxiliary battery malfunction appears on the dashboard. In most cases, the car runs and drives fine even with a bad auxiliary battery.
Does auxiliary battery start the car?
When the main battery is depleted, the auxiliary battery will kick in and continue to charge the car as needed. Just like the main battery, eventually the auxiliary battery will start to have issues and will need to be replaced.
Why do cars have auxiliary batteries?
Battery function The auxiliary battery on internal combustion engine vehicles is connected to the vehicles electrical system but isolated from the starter circuit. It prevents the voltage drop caused by engine starting from affecting the operation of the electrical system and ensures reliable cold starting.
What happens when auxiliary battery dies?
Having a battery that is dead will result in you not being able to crank the car when needed. Usually, the car will run once it has been jumped off, but will quickly die back out after it is turned off. Once the alternator stops, the cells in the battery will not be able to hold a charge and will cut off.
Can I drive without auxiliary battery?
It’s not recommended to drive when you’re experiencing issues with your auxiliary battery. However, it does not put you in any immediate danger as long as you don’t notice a decline in the overall handling and performance of your car.
Can you drive a Mercedes without the auxiliary battery?
Is it safe to drive with auxiliary battery malfunction? The answer is yes and no, it is always not good to drive with any kind of malfunction on your vehicle as you don’t know how it will affect car’s performance or other functions.
Does the alternator charge the auxiliary battery?
Every vehicle has an alternator. You can easily use your alternator to charge your second (auxiliary) battery simply by connecting the positive terminals of both batteries so that they’re in parallel.
How do you charge an auxiliary battery?
By connecting the positive terminals of both batteries, you can easily use your alternator to charge your auxiliary battery. Your electrical loads won’t drain your starting battery, and your auxiliary battery will only be charged when the engine is running, if you have an isolator.
How long does a Mercedes auxiliary battery last?
Properly cared for and maintained, you can expect anywhere from 18 months to 3 years of life from an auxiliary 12-volt battery. Much will depend on frequency of use, and how well the battery is protected. Rough roads can cause the cells to break down, reducing the lifespan.
What are the uses of auxiliary battery?
Auxiliary Battery Overview Auxiliary batteries vary in size and specification dependent on the demands placed on it by the vehicle electrical system and can be used as a safety back-up to support the main battery when required or to provide voltage for specific vehicle systems all of the time.
What does AUX mean on a alternator?
An auxiliary wound excitation system on an AC alternator works by having a separate second winding embedded into the main stator winding. This winding is used to independently power the AVR.
Can you charge a second battery with jumper cables?
Jumper cables can supply power via a functional battery from another car. Keep a set in your vehicle. Connecting your car’s battery to another car’s battery with jumper cables is a common way to recharge a battery. Attach the other red clip to the positive terminal on the battery that needs a charge.
Why do Mercedes have 2 batteries?
Why do Mercedes-Benz vehicles have two batteries? Two batteries are needed because it has too many electrical demands. The main starting battery is in the trunk and the secondary battery is located under the hood, near the windshield. The Mercedes auxiliary battery provides voltage to the stop/start function.
How much does it cost to replace an auxiliary battery in a Mercedes?
On average the auxiliary battery replacement will cost between $200 and $300 with parts and labor.
What does the auxiliary battery in a Mercedes do?
Auxiliary batteries work with your main starter battery, and as a backup battery in the event the main battery becomes disabled. It prevents your vehicle’s electrical components from dropping when starting/stopping your engine and keeps your radio, GPS, and other in-vehicle electrical components turned on.
What does W211 auxiliary battery do?
The main battery in W211 models is located in the center of the trunk, mounted in a well, below the trunk carpet. The auxiliary battery supplies power for a limited time if system charging or battery voltage drops. The battery control module monitors system voltage.
Can an auxiliary battery drain the main battery?
other accessories continue to draw power when the engine is off. However, simply wiring extra batteries into a vehicle’s electrical system can allow auxiliary batteries to drain power from the main battery, inhibiting engine starting and other essential functions.
How long does a Mercedes battery last?
As with most cars, you can expect to get 4 to 5 years out of your Mercedes-Benz car battery. While this offers a general guideline, your battery life can be impacted by: Weather Extremes: Hot temperatures can cause your battery’s fluid to evaporate while extreme cold can drain it of its power.
