How to Troubleshoot a Mercedes 430S

1. Locate the OBD port on the Mercedes. Look under the driver-side dash, under the steering column. Lift the flap covering the OBD port.
2. Plug the OBD tool into the port. Put the key in the ignition and turn the vehicle to the 'Start' position.
3. Wait until the OBD tool reads the vehicle trouble code. This code will be on the front of the OBD tool, on the small screen. Check the OBD manual for the meaning of the code that appeared on the screen.
4. Note the error code that you were given on the OBD tool and go to a certified mechanic or parts store, which can further advise you of what steps need to be taken to repair the Mercedes.