The battery was dead on 2015 Danali Terrain and now that it is charged up the dashboard monitor, radio do not turn on. what could be the problem?.
Check the radio fuse but you probably need to re-enter the radio code which can probably be found in the glove box.
Read your owners manual for details.
With the modern computers, if you disconnect the battery, it has to be re-programed back into the computer. If you don't find how to do it in the manual in the car information packets, go to the dealer and they should do it for you. While you're there, ask them if they have found out the reason so many Terrains are having issues with dead batteries. If they say they never heard of that problem, tell them to check this site as there are a ton of people experiencing the same issue as you had with the battery.
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