Mercedes-Benz Auxiliary Battery Malfunction
Mercedes-Benz, a well-known luxury car maker, has recently been at the heart of a debate about how some of their vehicles' batteries are set up. Mercedes-Benz currently uses a dual-battery system, which comprises the main vehicle battery as well as an auxiliary battery, in the majority of its vehicles.
Auxiliary battery malfunction is a common warning sign that Mercedes Benz owners occasionally see on their dashboards. This message may be rather frightening, especially if it appears while the driver is on the road.
The major culprit for this issue is typically a malfunctioning voltage converter, and when the auxiliary battery starts to malfunction, you may also receive a computer error notice that says "Stop vehicle shift to P leave engine running."
When either of these two notifications remains on the dashboard for an extended amount of time, the issue will become obvious and you should start looking into solutions.
The best approach to determine if the auxiliary battery is the cause of any of these error codes is to test if the car will start. If your Mercedes-Benz can start up and run with some restricted functionality, the secondary battery is probably the problem.
The use of an OBD scan tool, which enables you to examine the full diagnostic information about your car down to particular error codes so that you can be certain of what the issue is, is another technique to identify a potential auxiliary battery malfunction.
The Table of Content
- An Auxiliary Battery for Mercedes Benz: What Is It?
- What Is the Function of a Mercedes Auxiliary Battery?
- Where Is the Location of the Mercedes Benz's Auxiliary Battery?
- What Should You Do Next When the Mercedes Benz's Auxiliary Battery Malfunctions?
- How Can You Fix Problems With the Mercedes-Benz Auxiliary Battery?
- What Causes the Mercedes Benz's Auxilary Battery to Malfunction?
- What Kind of Mercedes Auxiliary Battery Does Your Car Have?
- Which Models of the Mercedes-Benz are Commonly Impacted By the Auxiliary Battery Malfunction?
- What Is Likely to Happen If the Dashboard Indicates an Auxiliary Battery Problem?
- How Much Will a New Auxiliary Battery for My Mercedes-Benz Cost?
- When the Auxiliary Battery Problem Warning Appears on Your Dashboard Computer, What Should You Do?
- How Can I Pick the Best Auxiliary Battery Replacement for My Mercedes Benz?
- What Does Auxiliary Battery N000000004039 for Mercedes-Benz Mean?
- What Does the Auxiliary Battery A0009829308 Do?
- Is It Possible to Recharge the N000000004039 Auxiliary Battery?
- Is It Safe to Operate a Vehicle While an Auxiliary Battery Malfunctions?
- The Conclusion
1. An Auxiliary Battery for Mercedes Benz: What Is It?
Depending on the model, year, and several other parameters, there are two distinct kinds of auxiliary batteries, also known as Mercedes secondary backup batteries, in Mercedes-Benz vehicles.
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For instance, the E class W211 S211 W212 S212 C207 A207 ML W166 GL X166 C class W204 S204 S class W220 W221 A class W176 W177 CLA W117 CLS W218 C257 Sprinter W906 Vito W639 W447 G class W463 G500 G55 G63 AMG cars have the small auxiliary battery located at the luggage compartment (boot, trunk) or under the front side upper cover at driver side.
To determine which battery is used in your Mercedes, you must first open the hood (bonnet) and trunk (boot). In the trunk, this component is typically found close to fuses. If, after checking these two locations, you were unable to find a small auxiliary battery, your car is likely using a voltage converter.
The stop-go function, among other things, is powered by the auxiliary battery, which controls and runs them. If the auxiliary battery fails, none of these features will operate.
Other models, such as the C class W205 C200 C220 C250 C300, have an auxiliary battery as well, however it functions more like a tiny module ballast, also called a voltage converter, and serves the same function as other types of batteries: to power up and operate extra automobile equipment.
2. What Is the Function of a Mercedes Auxiliary Battery?
Auxiliary batteries for Mercedes-Benz vehicles come in two different varieties. Some automobiles feature a micro battery, which is somewhat smaller than the primary (main) battery, while the auxiliary battery in other vehicles is entirely different.
The new C class W205 S205 C205 E Class W213 S213 GLC X253 C253 and S W222 class automobiles have been equipped with this unique form battery, also known as a voltage converter.
The new form of auxiliary battery, also known as a voltage converter or convertor, is entirely different from the previous generation auxiliary battery.
The majority of the cars' extra features and accessories, such as PDC sensors, multimedia, different radars, stop-start functionality, and so on, are powered by the auxiliary battery.
It has a lifespan, just like every other electrical module or component, and eventually, it will wear out and stop working.
3. Where Is the Location of the Mercedes Benz's Auxiliary Battery?
Depending on the automobile type, there are often three potential places for supplementary batteries.
The driver's side beneath the top side panel, the passenger side under the footwell light, and the trunk (boot) under the fuse box are the three primary locations.
4. What Should You Do Next When the Mercedes Benz's Auxiliary Battery Malfunctions?
The auxiliary battery is often found at the top of the front passenger footwell in newer Mercedes models. To access the battery region, you will need to remove some adjoining plastic moldings and pull up the carpet. The fastenings may be undone with a 10mm socket. Additionally, before starting the task, the primary battery needs to be disconnected.
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After removing the fasteners and the plastic cover, you may remove the voltage converter by pulling out a few tiny tabs. The capacitor, which is another name for the voltage converter, is readily available. It affects some contemporary Mercedes vehicles, including the C-Class (W205 S205 C205), S-Class (W222), E-Class (W213 S213 C238), and GLC-Class (X253, C253). Online pricing for the A205905341480 capacitor varies.
The removal process is then simply reversed. The voltage converter's two clips and leads need to be re-fastened, and the square plastic cover has to be bolted back on. When you reconnect any removed plastic trim pieces, make certain the carpet is properly placed.
Your car's battery should be located in the trunk (boot), next to the fuse box, unless it is not one of the S-class W221 R-class R251 ML W164 GL X164 models listed above.
The auxiliary battery for E-class W212 S212 C207 A207 A0009829308 is situated on the upper side panel on the driver's side; to reach it, you must remove the plastic protective cover.
The old N000000004039 auxiliary battery must then be removed from its original location and replaced. Once this is done, the error code for the auxiliary battery failure will automatically go away, negating the need for a subsequent visit to a dealer shop.
5. How Can You Fix Problems With the Mercedes-Benz Auxiliary Battery?
Finding out how to fix the auxiliary battery to get your car fully functional again comes after you've determined the reason for the issue. The Mercedes auxiliary battery is found inside the front footwell of the passenger seat, at the top, in Mercedes-Benz automobiles of more recent models.
In addition to removing the carpet, you will need to thoroughly unhook all connected components to obtain access to the battery. It is simple to access since the screws holding the battery to the storage component are designed to be removed using a 10mm socket.
To prevent any shortages or sparks, you should also unplug the connections from the primary car battery before removing the auxiliary battery. Peeling back a few tiny plastic tabs will allow you to start removing the voltage converter after all of the aforementioned procedures have been finished.
Don't mistake the words as they refer to the same component since the capacitor is another frequent name for the voltage converter. After finishing all of these steps, you may simply do them again in reverse order to put a new capacitor inside your car.
6. What Causes the Mercedes Benz's Auxilary Battery to Malfunction?
A warning message such as "auxiliary battery malfunction" or, in 2015 and subsequent models, a warning message such as "halt vehicle shift to P leave engine running" will appear when the auxiliary battery is unable to maintain a charge to recharge.
Both of these error messages are typical for Mercedes-Benz automobiles, and aside from the error message, the car typically functions and drives without issue.
If the vehicle starts and drives without issue, the auxiliary battery is to blame, but the dashboard keeps displaying the auxiliary battery malfunction error.
Mercedes-Benz has attempted to read the codes using a standard OBD-II scanner, but no fault codes have been shown. Since generic scanners cannot read Mercedes-Benz-specific fault codes, you will not be able to identify fault codes that suggest a faulty auxiliary battery using a generic scanner.
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The secondary battery will be the cause of the problem if the car still starts and certain features operate. The mechanical operations of the automobile are unaffected by the supplementary battery.
7. What Kind of Mercedes Auxiliary Battery Does Your Car Have?
You should be aware that Mercedes automobiles have three distinct types of auxiliary batteries. Once you've identified an auxiliary battery issue, it's crucial to gather the details before deciding to advance with a repair or a replacement because the positioning of the battery might vary depending on your unique make and model.
You must open the trunk as well as the hood of your car to see exactly which battery type is installed there. If you don't notice a little auxiliary battery nearby, your car doesn't employ a voltage converter; instead, there are fuses inside the trunk.
Your primary battery may be found behind the hood, where it can provide you with a short overview of the technology that your particular model employs. If there isn't a little auxiliary battery beneath your hood, your vehicle does not have one.
8. Which Models of the Mercedes-Benz are Commonly Impacted By the Auxiliary Battery Malfunction?
The following Mercedes-Benz vehicles are impacted by the auxiliary battery issue:
- The Mercedes Benz E-Class (W211, S211, W212, S212, C207, A207, ML W166, GL X166)
- The Mercedes Benz C-Class (W204, S204)
- The Mercedes Benz S-Class (W220, W221)
- The Mercedes Benz A-Class (W176, W177, CLA W117, CLS W218, C257)
- The Mercedes Benz Sprinters (W906 Vito, W639, W447)
- The Mercedes Benz B-Class (W246, W247)
- The Mercedes Benz G-Class (W463, G500, G55, G63 AMG)
- The Mercedes Benz C-Class (W205 S205 C205)
- The Mercedes Benz S-Class (W222)
- The Mercedes Benz E-Class (W213 S213 C238)
- The Mercedes Benz GLC-Class (X253 C253)
- The more recent model, which is not seen here
Check that area first when you start to suffer problems because all of these vehicles have a little auxiliary battery that is either concealed or just below the hood, dashboard, or spare tire box.
9. What Is Likely to Happen If the Dashboard Indicates an Auxiliary Battery Problem?
The auxiliary battery may begin to experience problems as a result of normal wear and tear, and these problems should be addressed right once to prevent more serious harm. The auxiliary battery has to be replaced if the car starts up correctly but you see warning lights on the dashboard computer screen which read "auxiliary battery problem."
If your vehicle's engine starts and runs normally but its electrically powered accessories, such as the car audio system, signal lights, or safety features like PRE-SAFE, Active Brake Assist, ATTENTION ASSIST, Blind Spot Assist, Lane Keeping Assist, Lane Keeping Assist PLUS, or Active LED Lighting, do not function, your auxiliary battery may be the cause. Your Mercedes MBUX features are very much dependent on the Auxiliary battery
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Additionally, fuel consumption and eco-start/stop might be impacted. Therefore, any malfunction signs you are experiencing are a warning that the auxiliary battery needs to be changed.
10. How Much Will a New Auxiliary Battery for My Mercedes-Benz Cost?
A Mercedes-Benz auxiliary battery replacement typically costs between $200 and $300. Labor expenses are predicted to range from $50 to $100; these estimates are subject to change.
You might want to take your car to a Mercedes repair facility or replace the entire auxiliary battery if this does not solve the issue. If it has lost charge, it might malfunction frequently much like the main battery.
11. When the Auxiliary Battery Problem Warning Appears on Your Dashboard Computer, What Should You Do?
Whether or not the car is still safe to drive is the main question that individuals have when they see the DTC error code on their display.
These tasks include powering your entertainment system, and the PDC sensors, enabling the radars to operate properly and giving actions for the start/stop function. Auxiliary batteries are in charge of controlling extension functions in your car.
These parts and functions of your car will be significantly affected if your auxiliary battery malfunctions.
However, the overall mobility, as well as the drivability of the vehicle, are rarely impacted by these parts. Nevertheless, you shouldn't put off fixing the issue for too long because doing so might result in later, more significant problems.
Like all other auto parts, auxiliary batteries deteriorate with use, therefore you will ultimately need to replace them.
Driving is not suggested if your auxiliary battery is giving you trouble. As long as you do not see a reduction in the general handling as well as the performance of your automobile, it is unlikely to place you through any immediate risk.
If it is only a malfunction, you might not even need to change your auxiliary battery; instead, you would simply need to make the necessary changes to the onboard computer's settings to enable it to interpret the battery signals correctly.
As a routine safety measure to prevent any significant concerns, you should only drive your car for roughly 100 km once you start to detect problems with the auxiliary battery.
You shouldn't experience any substantial changes in driving or functioning because the battery doesn't power any critical parts of the car, but if you do, you should try to fix the problem right away to prevent additional harm to your car.
12. How Can I Pick the Best Auxiliary Battery Replacement for My Mercedes Benz?
There are no set guidelines for selecting the finest auxiliary battery replacement for the Mercedes-Benz.
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You should be set to go as long as the battery is configured as a sealed 12V. Before the installation of any new auxiliary battery, verify sure it is suitable for your particular vehicle by checking the make and model.
If you've taken the time to read this article in its entirety, you ought to be ready to handle Mercedes-Benz auxiliary battery issues at this point.
Take note of our tips on how to diagnose issues, locate the auxiliary battery in the particular vehicle model, fix problems once they are identified, and select the appropriate part for your car so that you can continue driving safely.
To prevent further harm to your car, never exceed a 100km drive after noticing an auxiliary battery malfunction code on the car.
13. What Does Auxiliary Battery N000000004039 for Mercedes-Benz Mean?
The second model of auxiliary batteries, also known as backup batteries, are used in other Mercedes vehicles, including the GL X164, GL450, GL550, GL350, GL320, S-class W220, CL-class W216, CL550, CL600, R-class W251, ML-class W164, ML250, ML300, and many more. These batteries are 12V 1.2Ah lead-acid batteries.
This type is entirely distinct from a voltage transformer since, in contrast to previous versions, it resembles a conventional battery more. Its authentic parts were built in Taiwan.
N000000004039 is often found in the boot (trunk) section at the back of the vehicle, next to the fuse box.
14. What Does the Auxiliary Battery A0009829308 Do?
The battery A0009829308 is another option for Mercedes vehicles. It looks quite similar to the one mentioned above, however, it has a slightly different form and a different placement for the positive as well as negative terminals.
A0019822708, A0009829608, as well as A0049820008, are a few Mercedes-Benz OEM component numbers that are interchangeable and compatible with the A0009829308 battery.
As you can see, there are several OEM component numbers for backup batteries for Mercedes-Benz, such as A0009827008, A000 982 70 08, and so forth.
15. Is It Possible to Recharge the N000000004039 Auxiliary Battery?
As it uses lead-acid materials for the ub1213 battery, the legitimate Mercedes-Benz auxiliary battery N000000004039 12V 1.2Ah is rechargeable. However, just like every other car component, it has a lifespan and over time, it could completely fail or you could use all of its power from playing music that was left in the car, using too many accessories, or not driving for long distances enough.
16. Is It Safe to Operate a Vehicle While an Auxiliary Battery Malfunctions?
The answer is both yes and no. It is never a good idea to operate a vehicle that has any type of issue since you never know how it may impact other operations or performance.
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According to our knowledge and experience, when a new generation voltage converter, also known as an auxiliary battery, fails, it is safe to drive for at least 100 miles and possibly even more. This means that this component is primarily in charge of extra accessory functions like "stop/start" and other accessories that aren't crucial while you're driving, so you can continue to operate your Mercedes.
17. The Conclusion
The amazing list of technologies found in Mercedes-Benz models is well-known, and many of their contemporary vehicles include two batteries: a primary battery and an auxiliary battery. If there is a problem with this auxiliary battery, the dashboard will display an error message. Although the warning will be general, a little battery icon should be included.
A flashing onboard computer error fault message with the following quote, "auxiliary battery malfunction," or "stop vehicle shift to P leave the engine running" warning message is typically present when the voltage converter fails, and it causes a lot of confusion for Mercedes owners as to what it means. Continue reading to learn more!
The two most frequent fault codes for Mercedes-Benz vehicles are these two.
The fact that the automobile will still start and do certain tasks will let you know that the secondary battery is to blame. The mechanical operations of the automobile are unaffected by the supplementary battery. If you are doubtful, an OBD fault code reader should be able to identify the problem.
Finding out which auxiliary battery is installed in your car comes in second place on the priority list since there are two distinct types of batteries, which you will learn about later in our article. The most crucial thing is that we now know the problem and what to search for in the car.