Sienna V6-3.0L (1MZ-FE) (2003)
Customer Problem Analysis Check
(Sample) Engine control system check sheet
Symptom Confirmation and Diagnostic Trouble Code Check
SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the SIENNA fulfills various functions. The first function is the Diagnostic Trouble Code Check in which a malfunction in the
signal circuits to the ECU is stored in code in the ECU memory at the time of occurrence, to be output by the technician during troubleshooting. Another
function is the Input Signal Check which checks if the signals from various switches are sent to the ECU correctly
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can be performed effectively. Diagnostic functions
are incorporated in the following systems in the SIENNA.