Subaru Legacy 2002 Service Manual page 1901

DIAGNOSTIC PROCEDURE FOR NO-DIAGNOSTIC TROUBLE CODE (DTC)
Automatic Transmission (Diagnostics)
I: CHECK HOLD SWITCH.
S004794G78
DIAGNOSIS:
¼ LED does not come on when hold switch is ON.
¼ Hold switch circuit is open or shorted.
TROUBLE SYMPTOM:
¼ 2nd gear is not held.
¼ Failure of vehicle to start in 2nd gear except 1st range.
AT-132