How to Turn Off the Check Engine Light on a Passat
- 1). Locate the open onboard diagnostics (OBD) input connector to the left of the fuse panel under the steering column.
- 2). Plug the OBD scan tool into the connector under the dashboard.
- 3). Turn on the ignition but don't crank the engine.
- 4). Turn on the OBD scan tool.
- 5). Wait for the diagnostic tool display to read "OK," then press "Clear" on your diagnostic tool to clear all engine codes. This will turn off the Check Engine light.
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