Jeep Repair: Quick Question, jeep cherokee laredo, powertrain control module

Question
Hello,
     My sister has a 2001 "Jeep Cherokee Laredo." She had a diagnostic test of "P1494" and was told to take it to the dealership. Any suggestions on what this may be, would be greatly appreciated. Regards-Skyler

Answer
P1494-LEAK DETECTION PUMP SW OR MECHANICAL FAULT


POSSIBLE CAUSES
VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
LDP SWITCH SENSE CIRCUIT SHORTED TO GROUND
WIRING HARNESS INTERMITTENT
LDP VACUUM SUPPLY
FAULTY LEAK DETECTION PUMP
LDP SWITCH SENSE CIRCUIT OPEN
POWERTRAIN CONTROL MODULE