2020 Subaru Legacy BaseFACTORY OEM SERVICE PROCEDURE

Diagnostic Method

Judge as NG when the following conditions are established.

JUDGMENT VALUE SPECIFICATION (DIAGNOSIS 1-1 AND 1-2)

Malfunction Criteria Threshold Value
Instruction value Different from expected value
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 2

Malfunction Criteria Threshold Value
Process flow result The result and expected value do not match.
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 3

Malfunction Criteria Threshold Value
High integrated IC motor continuity cut demand Yes
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 4

Malfunction Criteria Threshold Value
Driving IC bus signal No change
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 5

Malfunction Criteria Threshold Value
Writing value to CAN register Not equal to the reading value
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 6

Malfunction Criteria Threshold Value
Absolute throttle position - Absolute throttle position memory when monitoring 1.6% or more
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 7

Malfunction Criteria Threshold Value
Data written in CPU Not equal to expected value
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 8

Malfunction Criteria Threshold Value
Data written in register Not equal to the reading value
JUDGMENT VALUE SPECIFICATION - DIAGNOSIS 9

Malfunction Criteria Threshold Value
Diagnostic Value (DV)
NOTE: Calculate DV as follows.
  • When (Actual engine output - Target engine output) is equal to or greater than Map value:

    DV = Z (Actual engine output - Target engine output)

  • When less than (Actual engine output - Target engine output) - Map value:

    DV = Z[(Actual engine output - Target engine output) - Map value]

 1900 kW or more
MAP SPECIFICATION

Vehicle speed (km/h (MPH)) 0 (0) 10 (6.25) 20 (12.5) 30 (18.7 5) 40 (25) 50 (31.2 5) 60 (37.5) 70.4 (43.7 5) 80.5 (50) 91 (56.2 5) 101 (62.5)
Engine output (kW) 26 26 26 26 30 40 60 85 120 160 200

Time needed for diagnosis: 

Diagnosis 1-1: 2 times

Diagnosis 1-2: 8 time(s)

Diagnosis 2: 504ms

Diagnosis 3: 48ms

Diagnosis 4: 2500ms

Diagnosis 5: Less than 1 s

Diagnosis 6: 24ms

Diagnosis 7: 2 times

Diagnosis 8: 2 times(s)

Diagnosis 9: Less than 1 s

Malfunction indicator light illumination  : Illuminates as soon as a malfunction occurs.

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.