Jump Starting And Charging Vehicles With Battery Management Systems

Jump starting and charging a 12 V battery with a battery management system (BMS) may not be as simple as connecting cables to the battery. Most newer vehicles are equipped with a BMS and may have specific instructions on how to jump start and charge the battery.

What is a battery management system? A BMS monitors the battery state of charge and all power entering and exiting the battery. Ensuring the battery state of charge is maintained appropriately prevents the battery from becoming discharged or over charged.

The BMS also communicates with the rest of the vehicle systems to ensure power is maintained at the correct voltage levels. The system allows the vehicle to identify if the battery is operating outside of its parameters, or if there are any issues. This is possible because vehicles with a BMS will typically have a sensor mounted to the negative battery terminal.

Unlike older vehicles, it is not as simple as attaching a positive and a negative clamp to the battery and jump starting or charging. Every make and model may have a specific procedure that should be followed.

When charging the vehicle battery, it is critical that the correct type of battery charger is used. Many of the 12 V batteries, like absorbed glass mat (AGM), can only be charged at low current levels and may have different cut-off voltages compared to traditional flooded cell batteries.

The charging procedure may require the leads be connected to points other than the battery terminals. This allows the BMS to monitor all energy going into the battery. If unmonitored energy is put into the battery, the BMS may not have accurate information as to the battery’s actual state of charge.

Jump starting and charging information can typically be found in the service manual and/or owner’s manual. If the vehicle-maker specifications and procedures are not followed, the battery and other electrical components could be damaged. Always follow vehicle-specific battery instructions to ensure a complete, safe, and quality repair.

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.

  • 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...

  • I-CAR Repairers Realm: Quick Stick Dent Removal - Coming Soon Friday, 13 June 2025

    I-CAR is having a discussion on Quick Stick dent removal.

  • 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.

  • Non-SRS Wiring Repairs: Rivian Thursday, 5 June 2025

    What is a non-SRS wiring repair? It is the repairing of an electrical component that is not part of the supplemental restraints system circuit (usually identified by yellow wire looms). As...