With Scan Tool

NOTE: While performing the following procedure, do not move the ride/shock select switch during testing. If switch is moved during testing, all subsequent trouble codes will be invalid.

1. Ensure ignition switch, headlamps, parking lamps and autolamps are in the OFF position.
2. Set ride/shock select switch into AUTO position.
3. Set scan tool, (Rotunda Super Star II 007-00019, 007-00028, or equivalent) into HOLD mode, either fast or slow format for status codes.
4. Connect scan tool to Automatic Ride Control (ARC) Diagnostic Link Connector (DLC) found at left front shock tower.
5. Turn scan tool ON, then place switch into TEST position. If using Rotunda Super Star II tester, ensure mode switch is in EEC-IV, MCU position.

NOTE: Read following procedures completely before starting vehicle to begin testing.

6. Start engine, then within 20 seconds:
7. Switch tester from TEST to HOLD then back to TEST within a period of less then five seconds.
8. Wait until all Diagnostic Trouble Codes (DTCs) have been recorded into scan tool.
9. Refer to Diagnostic Trouble Code Interpretation for DTC table and information on action to take.
10. Additional Quick Tests must be performed at this time, to check the following:
a. Steering Sensor.
b. Vehicle Speed Sensor.
c. Shock/Ride Select Switch.
d. Brake Sensor.
e. Acceleration Signal.
f. Dimming Function.