Circuit Description

WARNING: This page is about a different car, the 2003 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.

Throttle motor is operated by ECM and opens and closes throttle valve using a gear. Opening angle of throttle valve is detected by throttle position sensor which is mounted on throttle body. Throttle position sensor provides feedback to ECM to control throttle motor in order to control throttle valve opening angle properly in response to driving condition. If DTC is stored, ECM shuts down power for throttle motor and throttle valve is fully closed by return spring. Throttle valve is locked at a certain opening angle. Also, all electronically controlled throttle operation is cancelled until system returns to normal and ignition switch is turned off. Electrical throttle system does not use a throttle cable. P2102 will set when throttle control motor output duty is 80 percent or more and throttle control motor current is less than .5 ampere for 2 seconds. P2103 will set when throttle control motor current is 16 amperes or more. It will also set when throttle control motor current is 7 amperes or more for .6 seconds. Possible causes are:

Open in throttle control motor circuit (DTC P2102).
Short in throttle control motor circuit (DTC P2103).
Faulty throttle control motor.
Defective ECM.