2004 Infiniti G35 Service Engine Soon light

That has to do with the electronic throttle control. There is not a cable for the accelerator but a sensor that moves it.

HAs anyone moved the throttle plate for any reason?

The only way it could have been moved during the brake job is if someone intentionally went in there is see how dirty it was in an effort to sell a throttle cleaning service.

Electric throttle control actuator consists of throttle control motor, throttle position sensor. The throttle control motor is operated by the ECM and it opens and closes the throttle valve. The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feedback to the ECM to control the throttle control motor to make the throttle valve opening angle properly in response to driving condition.

A piece of carbon may be holding it open in which case it may be as simple as cleaning the throttle bore. However in cases such as a nissan, it will typically ruin the throttle body actuator. Not sure on yours, I wouldn't attempt to move it for fear of this.

IF the throttle wasn't cleaned then it may help. If not, it will need to be tested. A scanner is how the codes should be cleared and see if it returns.

Do call the brake shop and ask if they would have looked at it. It may state it on the bill if they recommended cleaning it, in which case it was likley moved at that point.

In some situations a problem cleared by itself, (such as a carbon piece stuck and then releasing) can re-test the system on it's own and may or may not turn off the light. So there may be no problem.

On the other hand there may be a problem that is there, may return and may re-set the light.

Essentially, by clearing the DTCs *diagnostic trouble codes), you are erasing the memory of the self-tests and findings of the computer. After driving, the systems go through self -tests to re-set the monitors. IT is not going to hurt anything by doing this unless you are going to take it in for diagnosing. Information is retained well beyond the code setting that may aid in troubleshooting. Freeze frame data for example is retained when the code sets. The data stream of the powertrain manangement is recorded when the code sets.