Q&A

 Master

It is most likely the Alternator. Usually the brushes wear down until they will not carry any electrical current on a Bosch Alternator. I would have a shop do a charging system check just to be sure though. It is not a cheap Alternator to buy and not very easy to install. The wiring goes bad pretty rarely and the fact that the light is on means that there is most of the needed circuit continuity in place.

I would never put in an after market Alternator in these cars. I used to work for Bosch. BMW, Mercedes etc need high quality parts. it is how they are engineered. Often you can just replace the brush pack on a Bosch Alternator. ($20) This is what have done many times. I have seen them go for 350,000 miles and more. have a sharp BMW tech fully inspect your charging system,. it can be a good German car independent shop, including a full systems scan and complete Charging System Voltage Drops and Battery ( both of them ) load tests and specific gravity measurements. Then you can repair your 740i once and repair it right. These cars are not cheap to keep on the road. I hope you realize this. Best of Luck!

Good Luck!

 Technician

Hi, Yes,Dann is right. But it could be both things the alternator or the wiring. If you need help with your car come visit us or call us for a consultation. We specialize in european cars and have all necessary diagnostic tools for these cars. You can read more about us at http://www.transartnc.com . We use only high quality parts and never sell the customer that he doesn't need for his repairs. Very reasonable prices.

 Rookie

right now my 745 is on the way to the bmw shop for repairs, mine had all this symptoms plus a bit of smoke and funky smell in the fire wall in the engine compartment, smells like electrical.