Diagnosis System
WARNING: This page is about a different car, the 2003 Lexus ES 300 and 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
- Turn the ignition switch ON. Check that the CRUISE MAIN indicator light comes on when the cruise control main switch is turned on and that the indicator light goes off when the main switch is turned OFF. See Fig 1. If the indicator check result is not normal, go to CRUISE MAIN INDICATOR LIGHT CIRCUIT under SYSTEM TESTS. If the indicator check result is normal, go to next step.
- If a malfunction occurs in the vehicle speed sensors or actuator, etc. during cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and turns on and off the CRUISE MAIN indicator light to inform the driver of a malfunction. See Fig 2. At the same time, the malfunction is stored in memory as a diagnostic trouble code.
- Check output of DTC using diagnosis check wire. See USING CRUISE INDICATOR LIGHT under RETRIEVING DIAGNOSTIC TROUBLE CODES.