BMW Battery Registration vs. Coding
The registration procedure clears the charging history of the old battery and tells your BMW that a new battery with the same specs as the old battery is installed. The Engine Control Unit (DME) can charge the battery properly.
Registration must be performed every time you change the battery on a 2002 and newer BMW. It lets the car know the battery installed is brand new.
If the new battery has the same specs or very close to the old battery (CCA, CA, Ah, battery type) no coding will be required.
In addition to the registration procedure, you will need to carry out coding if you change the battery capacity or type. Coding is required if the new battery has different specifications compared to the old battery installed in the car.
For example, if you install a battery with a higher or lower cranking Ampere rating, or switch between Lead Acid and an AGM battery, you will need to code (program) the DME. Otherwise, the DME may overcharge or undercharge the new battery, and therefore shorten the life of the battery.
Q: Why do I need to register a new battery?
A: The short answer is that BMW designed the charging system with an algorithm that varies the rate of charge by the age and type of the battery installed. Registering a new battery resets the algorithm back to optimal charging voltage for the specified battery.
The long answer: “The negative battery cable has an electronic control unit on the battery end of it called an intelligent battery sensor (IBS). The IBS measures the state of battery charge and sends this information to the ECU. The ECU uses this information to control how much charging voltage is needed from the alternator to support vehicle electricity needs. A battery deteriorates normally over time and depending upon service demands and driving profile. The IBS reads this and the ECU tells the charging system to increase voltage and amperage output incrementally as the battery matures. Therefore, at battery replacement time, if you don’t tell the ECU it has a new battery it will overcharge the new battery causing it to wear out faster.
The registration process takes place in the ECU, which is the main player in this system. Also, when the IBS sees that battery voltage is too low for normal vehicle operation it can start shutting down vehicle functions to conserve power while keeping the vehicle operational. This would be accompanied by a check control warning of excessive battery discharge.”
Q: Why do I need to “code” for a new battery?
A: The answer to this varies. You may not have to! That is, so long as you replace your old battery with an exact replacement. However, if you switch from a wet-cell type battery to an AGM type battery, or vice versa, you must code for the change.
AGM and wet-cell batteries require a different rate of charge output from the alternator. Moving between these two types without coding can lead to over-charging or under-charging.
Also, batteries have a discharge rating called amp hours (ah). You must specify to the DME what the “ah” rating of your battery is so the car can run the proper charging algorithm.
Top BMW Battery Registration Scan Tools:
To complete the BMW battery registration process yourself, you will first need an OBD2 scanner that can perform BMW battery registration. Here is a list of popular scanners that you can use to register a new BMW battery.
Foxwell NT510/NT520/NT530 for BMW
One of the most popular BMW scanners. The tool can be used to register a new BMW battery with similar specs compared to the previous battery. Installing a new battery with significantly different specs requires coding which is not currently available on Foxwell NT510 at the time of testing.
BMW ISTA Rheingold
Require a laptop, ISTA software and hardware interface (BMW ICOM, K+DCAN, ENET cable etc).
Autel Scanners (MaxiSys, TS608, MD808 Pro etc)
Professional Level Diagnostic Scanner. It can be used to program and code any type of battery including AGM and lead-acid, even if the replacement battery is significantly different than the original.
BMW INPA Software (INPA K+CAN)
Require a laptop and familiarity with INAP software. One of the cheapest scan tools able to register a BMW battery.
Carly App for BMW