Section 150 (Cruise Control Systems): Description

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Vehicle is equipped with air bag supplemental restraint system. Before attempting ANY repairs involving steering column, instrument panel or related components, see SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM in TOYOTA - AIR BAG RESTRAINT SYSTEMS article.

CAUTION: When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery.

Primary components of cruise control system are cruise control Electronic Control Unit (ECU), cruise control actuator, cruise control switch, stoplight switch, park/neutral position switch and necessary wiring. The cruise control ECU also receives input signals from the Engine Control Module, vehicle speed sensor and electronically controlled transmission solenoid. See Figure.

System allows vehicle to cruise at a desired speed greater than 25 MPH. Cruise control system will manually cancel control over vehicle speed when brake pedal is depressed, CANCEL switch is activated, transaxle is shifted into any gear except DRIVE, or cruise control system is turned off. Cruise control system will automatically cancel control over vehicle speed when cruise control actuator fails, short occurs in magnetic clutch of cruise control actuator, magnetic clutch of cruise control actuator becomes disconnected, STOP (15-amp) fuse blows out, vehicle speed slows to less than 25 MPH, vehicle speed drops to 10 MPH less than preset speed, and vehicle speed signal input is lost.

The cruise control system has a self-diagnostic function. During cruise control operation, CRUISE indicator light on instrument cluster should stay illuminated. If CRUISE indicator light begins flashing, turn cruise control system off and then back on. A fault in the system has been detected by the cruise control ECU if any of the following occur when the cruise control system is turned on again: CRUISE indicator light does not illuminate, CRUISE indicator light begins flashing or CRUISE indicator light goes out after being illuminated.

The cruise control ECU is responsible for diagnosis of the cruise control system. Diagnostic Trouble Codes (DTCs) are stored by cruise control ECU for diagnosis and retrieval. Begin diagnosis of cruise control system by performing Customer Problem Analysis (Cruise Control System Check List). See Figure. The CRUISE indicator light can be used to display DTCs, or a scan tool can be connected to Data Link Connector No. 3 (DLC3) for retrieval of diagnostic information.