Free Economy ShippingProduct Specifications for Marathon AUX-14 BCI Group Size 400 12V Auxiliary AGM Battery (200 CCA)
| BM Part #: | MAR-AUX-14 |
|---|---|
| Battery Polarity: |
|
| Voltage: | 12 Volt |
| Cold Cranking Amps: | 200 CCA |
| Capacity: | 12 Ah |
| Type: | AGM |
| Battery Size: | Group 400 |
| Length: | 5.9" |
| Width: | 3.4" |
| Height: | 5.7" |
| Shipping Weight: | 13.00Lbs |
| Warranty: | 1 Year |
- Original Equipment (OE) Standards: Engineered to meet or exceed the exact factory specifications for luxury auxiliary systems, ensuring a seamless fit and identical performance to dealership parts.
- Start-Stop System Optimization: Built to handle the rigorous cycling demands of modern Start-Stop technology, providing consistent power to safety sensors and GPS when the engine is off.
- High Cranking Performance: Delivers a reliable 200 Cold Cranking Amps (CCA), offering more robust auxiliary starting support than many standard 170A or 180A alternatives.
- Sealed AGM Technology: The Absorbed Glass Mat (AGM) design is 100% maintenance-free and spill-proof, making it safe for interior installation (trunks or under-seats).
- Vibration & Heat Resistance: Encased in a reinforced housing designed to withstand the extreme temperatures and vibrations found in high-performance engine bays.
Product Description
Professional Auxiliary Power for Advanced Vehicle Electronics
Modern luxury vehicles and hybrids rely on more than just a main starter battery. The Marathon AUX-14 (Group Size 400) is a specialized 12V AGM auxiliary battery designed to support critical systems like GPS, dashboard displays, and active safety sensors. It is the direct-fit replacement for the factory batteries found in millions of Mercedes-Benz, Infiniti, and Jeep vehicles.
If your vehicle displays an "Auxiliary Battery Malfunction" message, or your Start-Stop system is no longer engaging, a weak auxiliary battery is the most common cause. The AUX-14 provides a robust 200 CCA and a 12Ah–14Ah capacity, ensuring your vehicle's complex electronics receive stable power during engine-off cycles.
Engineered for Safety and Performance:
- Maintenance-Free AGM: No water to check and no acid leaks to worry about. This battery is factory-sealed and safe for installation in passenger compartments or trunks.
- Extended Cycle Life: Designed to withstand twice the cycling of a standard flooded battery, making it the ideal choice for fuel-saving "Auto-Stop" engines.
- Precision Dimensions: With a standard BCI Group 400 footprint (5.9" x 3.4" x 5.7"), it fits perfectly into your existing tray with no modifications.
Why Replace Both? The Two-Battery Solution
Modern luxury vehicles from Mercedes-Benz, Infiniti, and Jeep utilize a sophisticated dual-battery system. While the large main battery handles engine cranking, the AUX-14 auxiliary battery acts as a dedicated power source for your vehicle's computers, GPS, and safety sensors during "Auto-Stop" cycles.
The Benefits of Simultaneous Replacement:
- Restore Start-Stop Functionality: If your vehicle no longer shuts off at red lights, it's often because the system detects one battery is too weak to support a restart. Replacing both ensures the system operates as designed.
- Shared Lifespan: Your main and auxiliary batteries are exposed to the same heat and vibration. When one fails, the other is typically near the end of its life, too.
- Save on Labor: Many vehicles require a Battery Management System (BMS) reset after installation. Performing this reset once for both batteries saves time and dealership service fees.
Find your vehicle's primary starter battery below:
Cross Reference & Compatibility
| Manufacturer | Replaces Part Number(s) |
|---|---|
| Mercedes-Benz | A0009827008, A0009829308, A0009829608, 0009827008 |
| Infiniti | 24410-5DA1A, 244105DA1A |
| Chrysler / Jeep | 68340411AA, 04727450AA |
| Exide / Varta | ETX14-BS, EK131, AUX14 |
| BMW / Volvo | Various models requiring 12V/12Ah-14Ah backup |
| Vehicle Make | Common Compatible Models |
|---|---|
| Mercedes-Benz | E-Class (W211/W212), S-Class (W221/W222), ML, SLK, GLK, GLE |
| Infiniti | QX30 (2017–2019) |
| Jeep | Grand Cherokee, Wrangler, Cherokee (Auxiliary Start-Stop) |
| Chrysler / Dodge | Pacifica, Voyager, Durango |
