What was found
L XFLOW SOV CAUTION MESSAGE IN FLIGHT. RAN THE QRH. TRIED TO MANUAL CROSSFLOW FUEL TO THE RIGHT TANK AND DISCOVERED THE L XFLOW SOV FAILED OPEN. WE ATTEMPTED TO START THE APU DURING THE DESCENT BELOW 10,000 MSL, BUT EXPERIENCED A VERY STRONG SMELL OF JET FUEL INSIDE THE CABIN. WE IMMEDIATELY SHUTDOWN THE APU AND THE SMELL DISSIPATED. (FLIGHT 5615 - FILED CLOSED) PLEASE REFERENCE AML 888271 FOR CORRECTIVE ACTION TO THE L FLOX SOV CAUTION. PLEASE REFERENCE AML 888276 FOR CORRECTIVE ACTION TO THE FUEL ODOR IN CABIN DURING APU START ON DECENT.