Vehicle Speed Sensor: Operation

2002 Subaru Forester BaseSECTION Operation

As the driven key rotates, the magnet turns causing the magnetic field of the Hall IC to change.

The Hall IC generates a signal that corresponds to a change in the magnetic field.

One turn of the driven key in the speed sensor sends 4 pulses to the combination meter, engine control module and cruise control module.

Fig 1: Identifying Vehicle Speed Sensor Operation
G02861277Courtesy of SUBARU OF AMERICA, INC.
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When to See a Mechanic

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

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