The trunk (very back door) lock is broken, and the light is on for Service Engine Soon. I just put all new parts in the engine, passed smog, and now I have to call Triple A to jumpstart my vehicle every other week. I believe it is an electrical issue that could be related to the back lock not being all the way shut, as I have it tied with a rope. Other areas, such as the radio/CD player, won't work now, but I can turn it on from the steering wheel center.
This sounds as though you are having multiple problems that would need to be addressed. The broken latch may be the cause of the dead battery, but not the Check Engine Light illumination, or the radio not working; the radio may need to be removed and sent out for repair, or sent to a radio repair shop. I recommend that you have a mechanic, such as one from YourMechanic, come by and run a diagnostic on your Service Engine Soon Light issue, and fix or replace your broken door latch.
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