2000 S80 P0751 & Ck Engine Lt

[Cad4men]

I'm having a bit of a problem, Ck engine lt comes on and goes off, codes reported are P0751 & P1618 which fires the check engine light.
130K miles, 22 mpg, No problems in 3 years. It shifts all 4 gears just fine, so I don't think it is the solenoids. Any other ideas? I've got to get this thing inspected.
Thank you,
Jerry