Snik. low battery gives difficult start up, and sometimes dashboard errors. If you killed the battery dont use the power seats and that bs if you expect to charge it, AC on and just drive, hopefully at daytime without headlights so you get maximum charging.. drive the car at hwy speeds for a good 30 minutes, to fully charge battery.
A E9n BMW will light up a bunch of warning lights -- none of which are validly lit up! -- when battery voltage is very low. The battery needs a very good charge now, done either by driving continuously out on the highway for a couple hours, or (better) with an external charger (CTEK unit highly recommended!) . 11724 posts · Joined 2007. #7 · Mar 6, 2013. The BMW alternator is internally regulated, but it is "excited" by a 12V signal from the PCM rather than direct from the battery. That's why the PCM need to be advised when the battery is changed, so that the PCM controls charge rate appropriately. Can the regulator be changed without changing the Replaced the Contact relay on the fuse box (top-right) 3. Checked voltage on battery, alternator, jumping points, engine block, starter and got 12 volts when car is off (14 volts when on) 4. Made sure that the engine block is getting voltage, the grounding straps are not perfect but the engine is still getting the 12V. Merqy. Weird electronic behaviour - dead battery symptoms? 1. if I don't drive my car for a few days it almost always starts immediately with a single start button press, so that I am not able to turn ignition on - it'll just start, even though the brake pedal is not depressed. If I drive day by day it never happens.