The ability to shift out of Park is controlled by a Shiftlock Release micro-switch. You must have the key turned to acc or run position and step on the brake pedal to actuate the switch releasing the shift lock. Any failure of the electrical circuit to the micro-switch or a failure of the switch itself will prevent shifting from the Park position. It could also be caused by a weak or dead battery.
There is a manual release button just ahead of and to the right of the shift lever. Press and hold the release button and then press the button on the shift lever to move the lever out of the Park position.
Has recent work been performed?
Shift cable? or bar.
The transmission shift solenoid on a Volvo s80 is located in the gearbox. It is inside the side cover and not easy to reach.
Volvo is a great technology in vehicles. Shift light indicator mean the indication given, that the vehicle is now comfortable to shift the gear. For Example, the Volvo car is moving on 60 mph and you are moving on 4th gear the shift light indicator will blink reminding now you can shift a gear further mean you can move by gear 5.
Shift into the far left corner.
P0785 Shift/Timing Solenoid Malfunction/ 3-2 Shift Solenoid Circuit Electrical
So that you don't shift the gear selector by accident
Trouble code P0750 means: Shift Solenoid A
Your shift lock solenoid may be bad.
VERY CAREFULLY.
I am having the same problem on my 94. It will go into drive but that is it.
it has a self tensioner pulley No adjustment required