Federal

Accessing the On-Board Diagnostics (OBD) requires an impulse counter scan tool or the Mercedes Hand-Held Tester (HHT).

1. Using one of the above specified tools, extract fault codes from each individual control module. Refer to "How to Read Diagnostic Trouble Codes (DTCs)" under the system to be diagnosed.
2. Find correct fault code (DTC) in the applicable code chart and test suspect circuit or component as indicated in the "Test Step/Remedy" column.
3. Repair defective circuit or component.
4. Erase fault codes from each individual control module. Refer to "How to Clear Diagnostic Trouble Codes (DTCs)" under the system to be diagnosed.
5. Test drive vehicle and recheck fault codes.