<MISC> Y2K and ECUs (Longish...)

[chris@xxxxxxxxxxxxxxxxxxxx (Chris Blumenthal)]

If you deal with this issue in your work as I do, you are probably sick of
hearing about it. However, I didn't see any responses on this that seemed very
comprehensive...

Most everyone knows that the engine management systems in later model BMWs
consist of one or more computers, commonly known in the industry as "embedded"
systems. There are probably other, separate embedded subsystems in the more
recent cars (e.g., traction control, anti-lock brakes, navigation and security
systems, etc.).

To most of us, these functions are controlled by black boxes hidden away
somewhere in the car. Each one of these black boxes is a self contained
computer with its own operating system. You may scoff at the idea of your BMW
being affected by the Y2K problem, but unless you are familiar with these
operating systems, you don't know if they use date data for some purpose and if
so, whether there are any inherent limitations in the way in which such data is
stored or processed. The designers may have had some reason for wanting the ECU
to know the real time and date.

If there is a problem, it would likely be related to the software and not the
hardware. After all, software lives forever. How long ago was the first ECU
code written?  About the same time that some of the software we know to have
Y2K problems was written. How much of that early code is left in the current
ECU code?

People are looking carefully at embedded systems on airplanes because of this
issue. Of course, if the ECU in your BMW shuts down when the clock rolls over
on one of the Y2K-relevant dates, (most of) you will just coast to the side of
the road, not fall from the air.

The truth is out there... Jim C.?

Chris Blumenthal
'95 M3
'97 M3/4

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