Q: How to diagnose common problems with Toyota Solara and Toyota Avalon that have an electronically controlled throttle body,Cruise Control Module,Cruise Control Servo,Cruise Control Switch and cruise control system?
A: The covered vehicles in question have an electronically controlled throttle body, meaning there is no mechanical linkage or cable. Instead, the accelerator pedal is connected to the throttle body through wires, with the ECM acting as the intermediary. This setup also interfaces with the electronic cruise control system. To locate common problems, several general procedures can be followed. First, with the ignition switch turned on, the Cruise Control Switch,Cruise Control Module and Cruise Control Servo should be turned on as well, causing the CRUISE light on the instrument panel to illuminate and turn off when the switch is turned off. Checking the Fuses is the next step, and if any abnormalities are found, further diagnosis will require a scan tool to read diagnostic trouble codes for the cruise control system. The system also relies on inputs from the Vehicle Speed Sensor (VSS), and a test drive should be conducted to determine if the cruise control is now working. If it is not, it is recommended to take the vehicle to a dealer service department or an automotive electrical specialist for further diagnosis.