Reading Diagnostic Trouble Codes

Diagnostic Connector Location:

1. Test drive the vehicle for at least five minutes.

a. Be sure that the engine reaches normal operating temperature (approx. 176°F)
b. The engine speed must exceed 3000 RPM at least once.
c. The accelerator must be fully depressed at least once.
d. Verify that fuses 15, 18, and 21 are OK.
e. Verify that the air conditioning is switched "OFF".
f. Verify that the engine ground strap located near the ignition distributor is making a good connection.

2. After the test drive do not shut the engine "OFF", continue to run the engine at idle for an additional 2 minutes.

NOTE: If the engine will not run, operate the starter for at least six seconds.

3. Switch the ignition "OFF".

Self Constructed Led Test Light:

SELF CONSTRUCTED LED TEST LIGHT

Fault Code At The Diagnostic Connector:

4. Connect an LED test light between the black and blue connectors of the diagnostic connections as shown in the image.
5. Turn the ignition "ON".

NOTE: Do not attempt to start the engine.

6. To display memorized fault codes connect a fused jumper wire between the black and white connectors of the diagnostic connections for at least 4 seconds and then remove it; as shown in the image.

^ The LED will flash 4 digit codes. Each sequence of flash codes will represent 1 number of the code. For example, two flashes, a pause, then three flashes, a pause, then four flashes, a pause, then two flashes indicates a CODE 2-3-4-2 (oxygen sensor system fault). If more than one fault code exists they will be displayed by repeating step 6. Record all fault codes and refer to the FAULT CODE TABLES for fault location and possible causes. Repeat step 6 until CODE #4444 (no codes present) is displayed.

Refer to TESTING BY FAULT CODES for detailed test procedures.

ERASING FAULT CODES

7. After all fault codes have been displayed, reconnecting the jumper wire once again for a minimum of five seconds will erase the permanent fault memory.