Subaru Legacy 2004 Service Manual page 2613

AUTOMATIC TRANSMISSION (DIAGNOSTICS)
Engine cannot start on "P" or "N" range
Engine start other than "P" or "N" range
Engine stalls.
Engine stalls when shifting to "N" % "D" and "R" range.
General Diagnostic Table
Symptom
5AT(diag)-154
Problem parts
• Key switch and Starter
• Control cable adjustment
• Inhibitor switch
• CAN communication line
• TCM
• Key switch and Starter
• Control cable adjustment
• Inhibitor switch
• TCM
• Fluid level and condition
• Engine speed signal
• Turbine speed sensor
• Lock up solenoid valve
• Line pressure
• Fluid level and condition
• Engine speed signal
• Turbine speed sensor
• Lock up solenoid valve
• Line pressure