like greg says, computers on wheels. so it's possible that even though it
looks like a simple swap out (my guess, a 15-30 min procedure) there's
still the outside chance that version coding is needed.
e.g. i know that inthe photos above, when my seats were being changed out
the PSE pump needed the help of the MB SDS multiplexor.
PSE pump can be had for approx $300 and about the size of a small loaf
of raisin bread....under the rear seat, pax side on W210s