The battery in your vehicle is one of the most important members of your “team.” Its job is to provide 12v of power to crank your starter & thus start the engine. But that’s not all! Once the engine is running, the (IBS) Intelligent Battery Sensor (located on the battery) reports the state of health & state of charge to the “Captain” (ECU) Engine Control Unit known to BMW as the (DME) Digital Motor Electronics. The DME evaluates your (the driver) power consumption to balance how much power is needed by the occupants & adjusts accordingly.

For example, it’s a chilly morning when you start your BMW, so you turn on your heated seats, perhaps the windshield defogger, and the rear window defroster. It might still be dark out, so the (ALD) Automatic Light Detection system recognized the need for the headlights while enjoying the Harman-Kardon® sound system. Now the BMW Bi-Xenon lights turn on & you’re ready to drive off.

…..Where is all this power coming from? The DME is calculating the power needed based on the driver’s request. The DME then tells the variable alternator to increase its charge rate to a max of 15 Volts. (The average charge rate in a BMW 13.8-14.1Volts) and your standard vehicle is fixed with 13.6 volts. The DME next calls to the IBS through a unique communication signal to see the state of health of the battery… The IBS reports….. “Due to COVID-19, I’ve been poised & ready, self-testing the battery for the last 45 days without being started”. It does this to make sure the battery has sufficient charge to start the engine,” but now the battery needs help. The message from the IBS reads, “tell the alternator to work harder & provide more voltage to recharge the battery” Yet the DME knows that the alternator is providing the most power it can, given the circumstance. Now a “Battery Discharge” warning may illuminate in the dash or the infotainment system, known as the Control Display. The message may read,” “Contact your local BMW service center for more info.”

The driver now recognized there is something wrong with the electrical system of their complex BMW. Now it is time to find a qualified shop that can identify the concern & provide the best solution in the long term & cost-effective way. Once the vehicle is diagnosed correctly by a trained & qualified technician, they will have tested the battery, the charging system & performed a series of other tests to determine the best result on a case by case basis.  

In our example, The vehicle battery is more than five years old; the customer did not know of Bimmer PhD. They did not know that during our signature oil service, we test the battery and charge the battery with the correct application battery charger. After a full charge, we retest the battery to make sure it’s healthy & dependable.

At Bimmer PhD, a trained & certified BMW technician has the proper tools & knows upon replacing a late model BMW battery that it is CRUCIAL to take the extra steps to register the correct battery replacement of the battery to the DME. That way, the “Captain” (the) DME knows how to disperse the power or voltage available to the driver & occupant of the ultimate driving machine. 

Many of us are finding ourselves driving less during the pandemic. The benefit of reducing miles on your odometer can harm your vehicle in other ways, such as your battery. We at Bimmer PhD are committed to taking every step to care for your car even when driving it less. Our knowledgeable technicians are the best in the industry and want to keep you on the road without any hassles or inconveniences. Schedule an appointment today. Please contact us at 626-792-9222. We are located at 1539 E. Walnut St., Pasadena, CA 91106.

bmw battery health