Enter specific test mode by connecting or disconnecting read memory and/or test mode connectors as shown in the RELATIONSHIP BETWEEN MODES & CONNECTORS table. Connectors are located behind left side of dash. See Fig 1 .
Observe O2 sensor monitor light, located in ECU. Note trouble codes, if any. Long illumination periods of 1.2 seconds designate the tens digit in the numbered codes. Short illumination periods of .2 second designate the ones digit in the numbered codes.
Tens and one digits are separated by a .03-second interval of non illumination. Example: 3 long flashes (1.2 seconds each), followed by 5 short flashes (.02 second each) designate code 35.
Code is repeated after a break of 2 seconds, unless another code is present which will be displayed after the 2-second break. Once all codes have been displayed, sequence will repeat.

Fig 1: Location of Read Memory & Test Mode Connectors

Courtesy of SUBARU OF AMERICA, INC.

RELATIONSHIP BETWEEN MODES & CONNECTORS

Mode

Read Memory Connector

Test Mode Connector

U-CHECK ⁽¹⁾

Disconnected

READ MEMORY ⁽¹⁾

Connected

Disconnected

D-CHECK ⁽¹⁾

Disconnected

Connected

CLEAR MEMORY ⁽²⁾

Connected

⁽¹⁾	Key on, engine off.

⁽²⁾	Key on, engine running.

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.

Safety Warning

Retrieving Codes