How to Reset the Service Engine Light on a Toyota Sienna
- 1). Open the hood of your Toyota Sienna and loosen the retaining nut on the negative battery cable clamp using a socket wrench.
- 2). Slide the negative cable clamp off its battery terminal.
- 3). Wait 10 to 15 minutes and reconnect the battery cable clamp to the battery terminal.
- 4). Start the engine and allow it to run for 5 minutes while the Sienna's computer relearns the idle pattern. The "service engine" light will go out during this time.
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