On Mon, 02 Jan 2006 07:35:35 +1100, Franc Zabkar
wrote:


Yeah, I would have expected the ECU to retain the key IDs in some kind
of nonvolatile memory.

- Franc Zabkar


They do. It is the first thing to be corrupted when the power fails.
I know a P38 RangeRover has a complex proceedure involving a sequence
of key rotations (unigue to each ecu) to remove the immobiliser.
I have experience of a Mercedes having to go to the dealers for a
reset following a flat battery, I assume the NVR memories that tell it
nothing is faulty got corrupted.

I am a bit of a luddite with cars. My current car has 3 computers,
that "talk" on the CAN bus, and all have to agree to let the engine
start. The instruments are ecu controlled, so I had to drive with no
speedo or rev counter once, luckily a power off/on "fixed" it. The
throttle is electric, so there is a noticable delay between stomping
on the pedal and anything happening. This also means no blipping the
throttle to get low gears in the cold and makes the engine race on
upchanges.

Computers and cars don't mix.