Circuit Description
WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
When the idle switch is turned ON, a signal is sent to the ECU. The ECU uses this signal to correct the discrepancy between the throttle valve position and the actuator position sensor value to enable accurate cruise control at the set speed. If the idle switch is malfunctioning, problem symptoms also occur in the engine, so also inspect the engine. See Fig 1.
Detection Item
- Short in idle signal circuit.
Trouble Area
- Throttle position sensor.
- Wiring harness or connector between ECM and throttle position sensor.
- Harness or connector between cruise control ECU and ECM.
- Cruise control ECU.