48-Volt Mild Hybrid Systems: Mercedes-Benz

Mild hybrid systems are not new. They were some of the first hybrid vehicles to be put into production. The 48-volt mild hybrid system is now becoming more common among some vehicle makers. What consideration are there for repairing a vehicle equipped with a 48-volt mild hybrid system? Let’s see what Mercedes-Benz has to say.

Mercedes-Benz introduced the 48-volt system on late model vehicles equipped with a 256 or 264 6-cylinder engine. The 48-volt system is used to support systems such as the stop/start function, coolant pump, electric refrigerant compressor, and heated windshield. This helps reduce fuel consumption, aid in performance, and provide additional occupant comfort.

Per the Mercedes-Benz 48 V On-Board Electrical System Technology Guide:

"For this reason, the 12V on-board electrical system remains virtually unchanged. It is merely supplied by a 48V/12V DC/DC converter instead of by a 12V alternator."

Per Mercedes-Benz vehicle-specific repair information, Notes On Battery:

  • "A 48V connector may only be unplugged in de-energized state. The 48V on-board electrical system is de-energized if the 12V battery is disconnected for longer than 10 s."
  • 48V ground line is colored brown and purple

The OEM Hybrid and Electric Vehicle Disable Search features a battery layout and step-by-step directions to locate the procedure to disconnect the negative battery cables.

For additional Mercedes-Benz information, check out the Mercedes-Benz OEM Information page.

Additional I-CAR Collision Repair News you may find helpful:


Related I-CAR Courses

  • Repairer Driven News: Rivian Updates Door Handle Procedure Sunday, 4 February 2035

    Repairer Driven News (RDN) released an article featuring an updated Rivian procedure.

  • 2025 SkillsUSA National Competition Results Monday, 30 June 2025

    The 2025 SkillsUSA National Leadership and Skills Conference took place on June 26, 2025. Every year I-CAR sends volunteers (virtually in 2021) to judge the collision repair technology competition....

  • Ford/Lincoln Rocker Panel Reinforcement Sectioning Friday, 27 June 2025

    We are often asked, “Can I section this panel?” Let’s take a look at Ford/Lincoln vehicles and sectioning the rocker panel reinforcement.

  • Back-To-Basics: Backside Panel Refinish And Edging Thursday, 26 June 2025

    Sometimes, going back to the basics can make the difference between a quality repair and a failed repair. When repairing and refinishing, you might need to refinish the panel's backside and edges.

  • Hyundai Position Statement: Pre- And Post-Repair System Scanning - UPDATE Monday, 23 June 2025

    Hyundai released an updated position statement relating to pre- and post-repair system scanning.

  • App-Based Connected Services Considerations Tuesday, 17 June 2025

    Have you had an experience where the vehicle notified the owner that it was being moved while it was in your repair facility? App-based connected services are available from many vehicle makers and...

  • Digital Key Considerations Tuesday, 17 June 2025

    The intermingling of technology and automobiles continues, with digital key offerings from most vehicle makers. Digital keys utilize smartphone technology to expand vehicle access and owner...

  • Back-To-Basics: Tire Tread Pattern Wednesday, 11 June 2025

    Sometimes going back-to-basics can make the difference between a quality repair and a failed repair. Let’s see how to identify tire tread patterns and their repair considerations.

  • Corrosion Protection Guidelines: Ford/Lincoln - UPDATE Tuesday, 10 June 2025

    A key factor in collision repair is making long-lasting repairs. When a vehicle is repaired, many areas of corrosion protection are disturbed. This creates corrosion hot spots that, left untreated,...

  • Rivian Restraints Wiring Thursday, 5 June 2025

    The question is often asked, "Can supplemental restraints system wiring be repaired?" The answer is: it depends on the vehicle maker. Let's take a look at Rivian's position on this subject.