The main reason for the monitors not to set is a thermostat that is stuck open and the engine does not warm up within the prescribed time.
Here is a guide that will help you confirm the problem:
https://www.2carpros.com/articles/replace-thermostat
Here is what it will be like on your car.
Please let us know what you find.
Cheers, Ken
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Aug 25, 2017 at 1:20 PM