05 wrangler hunting and Idle trouble

My 2005 Wrangler x has been to the shop 2 times in the last month. Had the crank sensor replaced each time. The engine idles a little high when first starting then settles. However, if I turn on the A/C it runs up to 2k rpms when the a/c cycles on. With the a/c off she will settle out and then begins to hunt .5-1.5K rpms. also engine light comes on while driving and stays on. When I turned on the key this evening it flashed 10 times. Is there a way to get the engine codes from the light w/o going back to the dealer? I would like to have a better idea of what I'm dealing with when I take it back. Any help greatly appreciated.:runaround: Thanks!