Will a bad ECM cause the OBD2 not to work?

Good morning,

If the check engine light comes on with the key on and the fuel pump runs for 2 seconds, then the ECM is working and may not be the issue.

Does the engine run? If it does and cannot communicate, it may be the scan tool you are using. Try it on another car to see if it works.

As far as testing, special equipment is required for the actual testing to see if it is good. You could remove it and send it out and have it checked.

What is the exact issue with the car?

Roy

Okay, the first thing I would do is check the compression to be sure the timing is correct. You should have 140-160 pounds in each cylinder.

https://www.2carpros.com/articles/how-to-test-engine-compression

If you have spark and fuel, the ECM is working.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Roy

Okay, keep me updated with the results.

Roy

This sounds like the timing belt has failed and moved from its settings.

You need to remove the front cover and inspect it.

I attached the procedure for removing the belt and inspecting the timing marks. You most likely will find the belt teeth are missing.

https://www.2carpros.com/articles/how-a-timing-belt-works

Roy

Yes, the belt is off. Follow the instructions for replacing the belt and getting the correct marks lined up.

Roy

You will need to set the belt correctly and then do a compression test.

https://www.2carpros.com/articles/how-to-test-engine-compression

You need 140-160 pounds.

Roy