Reading and Clearing Diagnostic Trouble Codes

Fig. 1 Diagnostic readout tool C-4805:

The Diagnostic Test Mode is used to retrieve fault codes that may be stored in the computer. If a fault code is displayed, perform a close visual check of all vacuum and electrical connections before proceeding to further diagnosis component or system.
1. Connect diagnostic readout tool to electrical connector located on left shock tower, Fig. 1.
2. Move ``read/hold'' switch on tool to ``read'' position.
3. Place carburetor fast idle screw on highest step of fast idle cam to open carburetor switch.
4. Turn ignition switch to Run position. When Code 00 is displayed, move ``read/hold'' switch to ``hold'' position.
5. Note and record any fault codes that may appear. The display of fault codes may be stopped at any time by moving switch to the ``read'' position. When tool is switched back to ``hold'' position, the fault codes will continue to be displayed.