I have a 2007 XJR.　I have been wondering about the parking brake failure for some time now.
It picks up the ignition status with fault code C1D1426, which causes a communication failure. I tried replacing the battery, the module, and the actuator, but the symptoms remained the same. The meter panel will show the parking brake in yellow and flashing red, and the message center will show "Press the brake to apply the parking brake" and "Parking brake not applied".
Somebody please help me.

 

May be the (Bowden) cable(s) seized (partially) or the motor failed. Could be the module, not so likely.

 

Did you reset the parking brake after battery disconnect? you have to relearn the parking brake and windows after battery disconnect.