2020 Subaru Legacy BaseFACTORY OEM SERVICE PROCEDURE

Inspection Mode H

WARNING: This page is about a different variant/trim than selected.
DTC Description & trouble part Condition Number of driving cycles on the detecting condition
P0071 AMBIENT AIR TEMPERATURE SENSOR CIRCUIT "A" RANGE/PERFORMANCE
  • 6 hours or more have elapsed since ignition switch is OFF under a completely warmed up condition.
  • For models with block heater, at least 6 hours must have elapsed without operating the block heater.
 2
P0116 ENGINE COOLANT TEMPERATURE SENSOR 1 CIRCUIT RANGE/PERFORMANCE 2
P0196 ENGINE OIL TEMPERATURE SENSOR "A" RANGE/PERFORMANCE 2
P050A COLD START IDLE CONTROL SYSTEM PERFORMANCE - 2
P050B COLD START IGNITION TIMING PERFORMANCE - 2
P24B9 EVAP SYSTEM LEAK DETECTION PUMP PRESSURE SENSOR CIRCUIT RANGE/PERFORMANCE - 2
P24D6 EVAP SYSTEM PRESSURE SENSOR/SWITCH "B" CIRCUIT RANGE/PERFORMANCE - 2
  1. Check that the battery voltage is 12 V or more and fuel remains approx. half [20 - 40 L (5.3 - 10.6 US gal, 4.4 - 8.8 Imp gal)].
  2. Using the Subaru Select Monitor, perform the clear memory of [Engine Control System]. Refer to COMMON (DIAG)>CLEAR MEMORY .
  3. With the ignition switch ON (engine stopped), read the values in [Coolant Temp.] and [Intake Air Temp.]. Refer to COMMON (DIAG)>DATA MONITOR .
  4. If the values from step 3) satisfy the following conditions, idle the engine for two minutes or more.

    Condition: 

    |Engine coolant temperature - Intake air temperature| ≤ 5°C (9°F)

    NOTE:
    • If the conditions are not satisfied, turn the ignition switch to OFF and wait until the parameters are satisfied.
    • Hold the select lever in "P" range or "N" range at idling.
  5. Read the temporary code using the Subaru Select Monitor or general scan tool. Refer to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.