THE POWER SLIDING DOORS ON THE 2004 SIENNA FAIL EARLY, CAUSING SAFETY AND USABILITY ISSUES. THE POWER DOOR CABLE WEARS OUT EARLY DUE TO FAULTY COATING ON HE CABLE, FAULTY HINGES AND DOOR FREEZING. ONCE THE CABLE SNAPS, THE DOOR CAN SLIDE OPEN UPON ACCELERATION. DISABLING THE POWER FEATURE ALLOWS THE DOOR TO BE USED, BUT FALSELY CAUSES THE VEHICLE TO REGISTER THE DOOR AS CLOSED WHEN IT IS OPEN, ALLOWING THE CAR TO BE PUT IN GEAR AND DRIVEN WITHOUT THE DOOR PROPERLY LATCHED CLOSED. LOOSE PARTS FROM THE SNAPPED CABLE AND TORN CABLE JACKET EASILY LODGE IN THE WORKING MECHANISM, MAKING THE DOOR BEHAVE INCONSISTENTLY - SOMETIMES LATCHING, SOMETIMES NOT. WHEN NOT LATCHED, THE DOOR EASILY SLIDES FORWARD OR BACK IF THE VEHICLE IS PARKED ON A HILL, POTENTIALLY CAUSING INJURY. IN ADDITION, THE DOORS FREEZE CLOSED IN MODERATELY COLD (25 F) TEMPERATURES, CAUSING THEM TO OPEN PARTIALLY (A FEW MILLIMETERS). THIS CAUSES EXTRA STRAIN AND WEAR ON THE POWER DOOR CABLES AND CAN CAUSE THE VEHICLE TO REGISTER AN OPEN DOOR. IF THE DOOR IS LEFT IN THIS CONDITION, IT CAN MASK OTHER DOORS ACTUALLY BEING OPENED WHILE THE VEHICLE IS MOVING. THE PARTIAL OPENING ALSO CAUSES A MISALIGNMENT OF THE LOCKING MECHANISM, MAKING IT VERY DIFFICULT TO OPEN THE DOOR TO CORRECT THE PARTIAL OPENING. THE DOOR REPAIR WAS QUOTED BY MULTIPLE DEALERS AT MORE THAN $3000. A TSB (0085-09) IN EARLY 2009 OFFERED AN ALTERNATE METHOD OF REPAIR, BUT THE COST IS STILL MORE THAN $1700 PER DOOR. DEALERSHIPS HAVE BEEN UNWIL