2008 Jeep Liberty Electronic Throttle Control Warning Light

My Liberty is giving an ETC warning light but it is only lit when the key is in the ACC position. Once the vehicle is running the light goes off. This is NOT part of the normal light test during start-up, the light stays on, then goes away when running. Any ideas what is going on? The dealership could not find any codes. Thanks!

Along with saying they could not find any codes,did they say the system is working as designed?