Circuit Description

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

The speed sensor SP2 detects the rotation speed of the transmission output shaft and sends signals to the ECM. The ECM determines the vehicle speed based on these signals. An AC voltage is generated in the speed sensor SP2 coil as the parking gear mounted on the rear planetary gear assy rotates, and this voltage is sent to the ECM. The parking gear on the rear planetary gear is used as the timing rotor for this sensor. The gear shift point and lock-up timing are controlled by the ECM based on the signals from this vehicle speed sensor and the throttle position sensor signal.

Fig 1: Identifying Output Speed Sensor Circuit

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: DTC Chart

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Reference (Using an oscilloscope):

Check the waveform between terminals SP2+ and SP2- of the ECM connector.

Standard: Refer to the illustration

OSCILLOSCOPE REFERENCE CHART

Terminal	SP2+ - SP2-
Tool setting	2V/DIV, 20ms/DIV
Vehicle condition	Vehicle speed 20 km/h (12 mph)

Fig 3: Identifying Waveform