Four problems related to warning light on have been reported for the 2004 BMW 5 Series. The most recently reported issues are listed below.
Deactivation of the passenger air bag and the illumination of both the air bag warning light and the passenger air bag light.
The front passenger seat sensor triggers the safety warning light on all the time. It may affect the airbag operable. This is a known issue and was subject of a voluntary recall program in 2008 by BMW. Despite many other car owners (as evidenced by complaints to NHTSA and online car forums), including myself, having this issue as described within the recall program for cars of the make and year of the production, only 200k within a specific VIN range were recalled.
The contact owns a 2004 BMW 545i (na). The contact stated while driving approximately 35 mph, the front passenger side air bag warning light illuminated. The malfunction continued until the engine was shut off. The failure occurred whenever the vehicle was in operation. The vehicle was taken to the dealer where they informed that the air bag senor would need to be replaced. The vehicle was not repaired. The failure mileage was approximately 91,000.
2004 BMW 530 I. The consumer complained about several electrical problems, such as air bag warning light coming on/windows rolling down and then malfunctioning/trunk opening, and halo lights staying on. The onstar or sos systems was not working. Took the vehicle to the dealership. The manufacturer considered this vehicle a lemon. The dealership and manufacturer were not complying with the lemon law. This process was to buy back the vehicle. They were taking too long to resolve this matter.