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Q: Swaped used ecm for original, sienna will not start, do I need to take it to the dealer to reprogram?

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2004 Sienna. Rat chewed wire from sensor plug #1. Following steps from a mechanic I fixed the wires, traced the wire to the ecm and the ecm was not sending signal to the sensor. Had a missfire cylinder code on #1. Bought a used ecm, identical, same part number. Swaped ecm with battery unhooked, hooked battery turn the key for 5min. Tryed it and will not start, it will crank and try to start but it dies. Do I need to take it to the dealer to reprogram or is there something else I could try? Thank you

You may not be able to have the ECM you purchased used reprogrammed. You would need to check with a dealer. Some cannot be swapped from one vehicle to another. They function this way so that parts could not be stolen and reused. Check to see if the dealer can do the reprogram on this one. It will not start until this is done. If you’d like a second opinion on this, consider YourMechanic, as a certified technician can diagnose your starting issue firsthand and suggest what to do from there.

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