There are multiple reasons why the Volvo brake to transmission interconnect switch can fail. In my case it was because of rain. I inadvertently left the sun-roof of my Volvo S-40 open just prior to a rain storm. The result was that the brake to transmission interconnect switch got wet and would not respond correctly.
The brake to transmission interconnect switch is located in the console of Volvo’s automatic transmission. In addition to the switch is a manual override. The manual override is located under the small door that can be seen just below the D position on the the automatic transmission.
In order to engage the manual override you will need a slender, straight tool that you will use to engage the manual override. I used the gauge from my tire pressure gauge.
First you lift the flap on the console the covers the manual override. You then insert the tool into the opening to about 5 cm. You should feel a little tension at this distance, gently push past the tension. At this point you have now engaged the manual override and you should be able to move the transmission out of park.
You should not attempt to use the manual override until you are sure that it is safe to take your car out of park.





