I was at the dealer's today picking up some plastic trim clips and talked to the service guys. Amazingly, only one even knew what a PNP switch was!!

He was amazed that the car wasn't operating only in limp-home 3rd gear. He said that the fault code would have to be cleared with a code scanner even after switch replacement when I asked if disconnecting the battery would clear the code. He offered that if the car is not driven or every gear is selected for awhile (a week or more) that it is very common to have a problem with the PNP switch if it's more than 2 years old (dirt on the contacts).

On BMWs there's a fuse that if removed would clear codes (without screwing the code-radio up as disconnecting the battery does). I don't know if Volvo has a similar fuse? Anyone know??

Anyway, when returning home, I started the car and shifted out of park, then shut the car off. Then I moved the shifter back and forth about a dozen times to see if that would clean the switch contacts. Restareted the car, and bingo-NO FLASHING LIGHTS. We'll see how long this lasts. At least I know it's not a "real" tranny fault.

By the way, SHOULD it be necessary to clear a tranny fault after PNP replacement, and when replacing the switch, does the tranny shifter have to be in a particular gear, or does it auto-index once it's installed and the shifter is moved through the full range of motion?

Thanks to all who responded to my questions.

Bob