Check engine light?

I would take a test light connected to battery positive. Go to the ECM and touch the test light to the Green with orange striped wire at terminal A18. It is the ground side of the MIL circuit. If the test light turns on the ECU driver transistor is the problem, and it would take replacing the ECU to turn out the light.
This is the OE circuit diagram on the control side. The side that goes to K is the battery feed that goes to fuse 9. So, you have power from fuse 9, that goes into the dash to feed numerous items the MIL included. Then from the other side of the MIL the Green orange wire goes to the ECM which turns the light on by grounding it. As you have an issue where the light is staying on then we can tell that the power side to the dash and light is okay. The ground side then would be the issue. That is the Green orange wire. So, you can test it at the ECM. You could also test it by doing a bit more invasive test, simply find that wire at the ECM and cut it without touching anything else. It can be reconnected after the test. If you cut it an inch or two away from the ECM and the light stays on, then the wire is grounded someplace where it runs to the dash. If it goes out, then it's the ECU.

We will be here.