Reading Diagnostic Trouble Codes

Fig. 18 Overhead Chassis View:

The self-diagnosis system operates in two modes; a U-check mode and a D-check mode. In the U-check mode, those components necessary for proper starting and drive operation are monitored. A malfunction detected while operating in the U-check mode will cause the ECS warning light to illuminate, indicating the need for further diagnosis.
To further diagnose the system, the D-check mode must be accessed. This is accomplished by connecting the green jumper wire connectors, Fig. 18 (ignition OFF) located under the instrument panel (driver's side). Then turn the ignition switch to ON. Any stored trouble codes will then be displayed as a series of flashes of the oxygen monitor LED lamp on the control unit. When reading the trouble codes display, the first digit of the code will be represented by a long pause of the light and the second digit will be displayed as a short flash. For example, Code 32 would be represented by three long flashes and two short flashes.
All trouble codes are stored in the control unit's memory. Upon completion of necessary repairs, the code will automatically be cleared from memory and the system will return to normal operation.