There is a solenoid in the shift assembly that sounds like it burnt out. You have to take the center console out to replace it. It sounds like yours burnt out in the "in" position. I had the same issue but it burnt out in the "out" postion and the car would not shift out of park. It is around $150 ...

Any idea why I'm able to shift from park without stepping on the brake, seems it is a safety issue.

New to forum, thanks.

2000 S80 T6
I had all codes cleared by Autozone after ABS module rebuild, soon after, the CEL came on. The car was scanned by Advanced Auto, the print out shows the following result.

DTC (Codes)

P0036
H02S Bank 1 Sen 2
Heater Circuit

P0136
02 Sensor
Circuit ...