Without Scan Tool
DTC CHECK (SENSOR CHECK)a. Perform an indicator check. After the indicator check is completed, the system enters the DTC check mode automatically.
b. Read the code displayed on the panel. Refer to the list of codes on Diagnostic Trouble Code Chart when reading the codes. (Trouble codes are output at the temperature display.)
c. If the slower display is desired, press the UPDr switch and change it to stepped operation. Each time the UPDr switch is pressed, the display changes by 1 step.