Disconnect the ground cable from battery. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
Disconnect the connector from ECM in numerical order as shown in the figure.

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Attach the ST between the ECM, engine wiring harness and the bulkhead wiring harness, Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .
Special Tool:

CHECK BOARD (18460AA150)
Connect the battery ground terminal, Ref. to REPAIR CONTENTS>NOTE>BATTERY .
Turn the ignition switch to ON. (Engine OFF)

Measure the voltage between ECM connector terminals.

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Throttle sensor	Accelerator pedal	Terminal No.	Standard
Main	Not depressed (full closed)	34 (+) and 20 (-)	Approx. 0.7 V
Main	Depressed (full opened)	34 (+) and 20 (-)	Approx. 3.9 V
Sub	Not depressed (full closed)	32 (+) and 20 (-)	Approx. 4.4 V
Sub	Depressed (full opened)	32 (+) and 20 (-)	Approx. 1.1 V

NOTE: For installation procedures of ECM connectors, refer to Engine Control Module (ECM). Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>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)