With Message Center

NOTE: It may be necessary to service non-EEC-IV faults before running the quick test.
Continuous codes recorded in this step will be used for diagnosis in ADDRESS CONTINUOUS MEMORY DTC after a pass code is received in both Key On Engine Off (KOEO) and Key On Engine Running (KOER) self-tests.
Deviation from this procedure may cause false codes to be output.

1. START engine and bring to normal operating temperature.
NOTE: If engine will not start or stalls after starting, proceed with the Key On Engine Off (KOEO) self test.
2. Turn the key OFF, then wait ten seconds.

Electronic Instrument Cluster Center In Self Test Mode:

3. Depress the Gauge Select, English Metric, and Speed Alarm buttons and hold them down.
4. With buttons depressed, turn ignition switch to ON position.
5. Release the three buttons, then press the Gauge Select button (typically three times) until cluster mode "dEALEr4" is displayed.

Jumper Wire Installed Between Pin #2 And Self Test Input (STI):

6. ACTIVATE self test by jumpering STI to SIG RTN at the DLC and STI connectors, or connect a scan tool to the vehicle and initiate self test. DTC output will be displayed on the message center.
7. Record all codes received.
8. Turn the ignition key OFF and DEACTIVATE the self test.
9. If a pass code (11 or 111) is received for hard codes (11/111-10-any code), proceed with the next test step. Key ON Engine Running (KOER) Self-Test
If any hard codes are received, refer to the appropriate diagnostic trouble code chart for diagnostic path. Manufacturer Code Charts