Disconnect the ground terminal from battery sensor. Refer to REPAIR CONTENTS>NOTE>BATTERY .
Disconnect the connector from ECM. Refer to Fuel Injection (Fuel Systems) (H4DO)>Engine Control Module (ECM)>REMOVAL .
Attach the ST between the ECM, engine wiring harness and the bulkhead wiring harness. Refer to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .
Special tool:

CHECK BOARD (18460AA180)
Connect the ground terminal to battery sensor. Refer to REPAIR CONTENTS>NOTE>BATTERY .
Turn the ignition switch to ON. (Engine OFF)

Measure the voltage between ECM connector terminals.

Courtesy of SUBARU OF AMERICA, INC.

Throttle sensor	Accelerator pedal	Terminal No.	Standard
Main	Not depressed (full closed)	29 (+) and 30 (-)	Approx. 0.6 - 1.2 V
Main	Depressed (full opened)	29 (+) and 30 (-)	Approx. 3.8 - 4.4 V
Sub	Not depressed (full closed)	43 (+) and 30 (-)	Approx. 1.4 - 2.0 V
Sub	Depressed (full opened)	43 (+) and 30 (-)	Approx. 4.0 - 4.6 V

After inspection, install the related parts in the reverse order of removal.
NOTE: For installation procedures of ECM connectors, refer to Fuel Injection (Fuel Systems) (H4DO)>Engine Control Module (ECM)>INSTALLATION .

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

Throttle Sensor (Method With Circuit Tester)