Thank you for the donation.
This is the type of problem that is never easy to diagnose and rectify.
Firstly you should get a scanned done to retrieve the trouble code for the Check engine showing. You should be able to get a scan done free at your local Autozone parts outlet.
Possible causes for the problem could be a bad ground or wrong wiring.
Do you have the wiring schematic for the XMtuner and were they installed correctly?
Do you have a schematic of the wiring system for the oem radio harness?
Friday, August 14th, 2009 AT 11:37 AM