Subaru Legacy 2003 Service Manual page 1851

ENGINE (DIAGNOSTICS)
(1) Front oxygen (A/F) sensor
(2) Front catalytic converter
ELECTRICAL COMPONENTS LOCATION
(2)
(1)
(3) Rear oxygen sensor
(4) Rear catalytic converter
(1)
EN-00968
(3)
EN-00969
EN(H4DOSTC)-12
(4)
(3)
EN-00967
(2)
EN-00970
(4)
EN-00971