My thanks to David, Walt P., S'V', Eviltwin; you have taken me out of the panic mode, and I am going to try replacing the PNP. Hopefully, I can follow your steps to help other Brickboarders.

By reading the FAQ and messages, the PNP issue goes back many years. I was somewhat surprised that VOLVO let it happen year after year. I don't have much bitter feeling, especially with your warm and informative suggestions; I am just wondering whether it's true that M30-40 'tranny' is basically a proven Lexus transmission. If so, why one is known as quite solid and the other were requiring PNP replacement with very few exceptions.

Also, do you suggest me to always have a spare PNP in hand? Does any vendor make a better PNP?

Last but least, how do you feel about the process of cleaning the switch contacts and re-use the PNP? Do they carry much current because the voltage is 12 volt?

Thanks.

PH.