If my XK had a crotch, I'd kick it !!!!!

[brand0n]

P0841 Transmission Fluid Pressure Sensor/Switch A Circuit Range/Performance
Anyone have this code? Worst part is trans was fine but wanted to do preventative maintenance (filters). i probably caused this
checked fluid and it was frothy on the stick

[Matt]

Hey man.... it COULD be coincidental...

But here's the list of possible causes.

LOSS OF PRIME AND/OR TRANSMISSION CONTROL RELAY DTC PRESENT
LOW FLUID LEVEL
LOW LINE PRESSURE
REVERSE CARRIER SNAP RING DISLODGED
CRACKED OR MISINSTALLED PRIMARY OIL FILTER OR FILTER SEAL
STICKING MAIN REGULATOR VALVE IN PUMP VALVE BODY
NO. 1 CHECK BALL CUT OR DAMAGED
WIRING AND CONNECTORS
(T50) LR PRESSURE SWITCH SENSE CIRCUIT OPEN
(T50) LR PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
(T50) LR PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
TRANSMISSION SOLENOID/TRS ASSEMBLY
POWERTRAIN CONTROL MODULE

Since you did drop your pan twice, the 2nd time to fix the seal you messed up, I'd have to start there in thinking its related. Did you double gasket the filter that looks like an oil filter?

Did you hit any lines trying to screw with that PITA trans filter seal?

Hell.... like Andrew said in the first reply- did you properly refill your trans? check the fluid level again, when its hot, on a level surface, and in Park. (ignore the instructions on the dipstick).