How to Resolve the Auxiliary Battery Malfunction in Mercedes-Benz?
2 Answers
Mercedes-Benz auxiliary battery malfunction can be resolved by visiting an authorized 4S dealership for repairs. The causes of auxiliary battery malfunction include: 1. Battery damage; 2. Wiring issues; 3. Control circuit problems. Models under the Mercedes-Benz brand include: Mercedes-Benz E-Class, S-Class, G-Class, C-Class, Maybach, etc. Taking the E-Class as an example, its body dimensions are: length 5078mm, width 1860mm, height 1484mm, with a wheelbase of 3079mm. The E-Class is equipped with a 1.5T turbocharged engine, delivering a maximum power of 135kW at 5800 to 6100 rpm, paired with a 9-speed automatic transmission.
I've been driving a Mercedes for several years, and last summer the auxiliary battery warning light came on, nearly causing a big problem. First, the auto start-stop system stopped working—the car wouldn't shut off at red lights, the AC fan was noisy, and even the windshield wipers were sluggish. This kind of issue is quite common, usually caused by an aging or low-charge battery. In Mercedes, the auxiliary battery is hidden under the trunk and powers electronic features like SOS emergency services, start-stop, and navigation. I replaced the battery myself with the OEM-recommended AGM model—just remove the cover panel to access it. After replacement, the light stayed on because the system settings needed to be reset with a specialized diagnostic tool. I rushed to the dealership, where the technician fixed it in minutes. It cost a bit, but the problem was solved. Since then, I check the battery voltage every six months to avoid failures in rainy weather. Mercedes' electronic systems are smart but delicate—prevention is cheaper than repairs.
