Description of On-Board Diagnostics

Diagnostic And Check Connector ID:

Diagnostic Connector Location:

MODE DESCRIPTION
The self-diagnosis system operates in two modes: a Regular Mode (U-check mode) and a Test Mode (D-check mode). In the regular mode, only those components necessary for proper starting and drive operation are monitored. A malfunction detected while operating in the regular mode will cause the ESC warning light to illuminate, indicating the need for further diagnosis.

To further diagnose the system, the test mode (D-check) must be accessed. This is accomplished by connecting the Test Mode Connector, Fig. 1. with the ignition switch in the ON position. Any stored trouble codes will then be displayed in a series of flashes of the oxygen monitor LED lamp on the control unit. When reading the trouble code display, the first digit of the code will be represented by a 1.2 second flash and the second digit by a .2 second flash. Trouble code 23 is displayed as two 1.2 second flashes and three .2 second flashes.

Trouble codes are displayed repeatedly and when multiple problems are detected trouble codes are displayed repeatedly in numerical order.

CLEARING CODES
All trouble codes are stored in the control unit's memory. Upon completion of necessary corrective action, the code(s) will automatically be cleared from memory and the system will return to normal operation.