How to Reset the ECU in a 1994 Buick
- 1). Open the hood on the Buick by pulling the hood release latch located on the lower kick panel under the dash on the driver's side of the vehicle.
- 2). Disconnect the negative battery cable from the battery terminal with an adjustable wrench. This removes electrical current from the ECU and causes it to reset.
- 3). Reconnect the negative battery cable to the battery terminal after a couple of minutes. This restores power to the ECU.
- 4). Drive the vehicle a total of 50 miles. The ECU relearns the factory settings and completes several diagnostics over the 50 miles.
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