comp 290:: BMW 745 Bug
 
Software Bug

BMW 745i software Defect: 

"On certain passenger vehicles, due to a software error, a desynchronization of the valvetronic motors for engine banks I and II may occur. If this occurs, the engine could stall. In those cases, the driver may not be able to restart the engine. Depending on the level of engine roughness, or stalling, as well as traffic conditions and the driver’s reactions, this could lead to a crash."

Official recall documentation (NHTSA #03V-240)

The BMW 745i had a software bug (fixed in recall), which in rare cases could stall the engine and lead to a catastrophic accident. The bug in the digital engine management control unit would cause a desynchronization between the two valve banks in the Valvetronic engine. My speculation is that the problem is caused by improper syncronization between the two digital electronic control units (ECU) each controlling one valve bank [Auto-tech daily]. The bug is rare, recalls common in the automobile industry, and therefore of manageable impact for BMW. 

Slide presentation

Economic cost
 
Involved parties
  • BMW – Damaged reputation, cover costs of recall (administration and implementation), fixing problem, 
  • Bosch provided control mechanism
  • BMW retailers – Damaged reputation, more difficult to convince customers to buy BMW. 
Preventatable?
"Non-massive, non-high performance, distributed computing: selected issues" by Albert Benvenist
Explain problem: 70 processors in BMW
Suggest development with formal specification
References 
Description of software bug: Economic cost of recall


Technical details of BMW engine


 
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dorian miller, 9/22/2002