Today when I applied the brake pedal, it would not release, the pedal remained down. The brakes were totally engaged and had to drive to a local shop (1/4 km) at full power. The shop is not familiar with 1995 Jaguar XJR Canadian Model. Does anyone have any suggestions?

 

booster or the pushrod got stuck on something

 

To roll the vehicle I would stay away from removing a fliud brake line least the later complications of properly bleeding the brake lines and if the shop can restore no air in brake lines

You might remove the vacuum hose from the booster and see if it lightens up on the brake force for small shop movements but not road ready or safe

You would have to insert a bolt in the open hose end least a small engine regulation caused by a vacuum leak

The proper brake system bleeding procedure will be coming later as a PDF or someone can walk you through it with the complications of the anti - skid module

 

See section 12 in PDF below

Bleeding instructions section 12 . 4