SPN-3490 Aftertreatment purge air actuator

[JimT]

could you add a little more information about your truck. You say it's an X15, what year exactly?

I've had that code repeatedly pop up on my cm2250. It was intermittent and at the end of the day I never did figure out what the actual problem was. I'm guessing, in my case, that there was a bad wire or ground somewhere since it would only happen sometimes and never while trying to troubleshoot it! I indirectly solved the problem by no longer needed that system to function.

You may already know, but there are specific troubleshooting steps to follow for this code. As this part interacts with air, fuel and electrical systems, you'll need to look up the correct code and troubleshooting steps for your particular engine via quickserve.