ECM is a major issue , that is correct and you might need replacement
But first unplug the ECM ( I sent a picture location) inspect the electrical connector and look for any backed out pins not making a good contact ,burned & melted wires on connector , get some electrical contact cleaner and spray in between the connector & the ECM.
when changing the ecm you will needed programmed by dealer to work.
or you can send yours in for a rebuild . ALLCOMPUTERRESOURCES.COM . is a good website ,where you send yours in ,you supply the vin # and mileage & they send it back to you ,and it will plug & play ,no dealer programming needed .
Let me know if you need anything else on it , just reply back here & we can continue.
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