u/LunaLockerlicker

Car wouldn't start this morning. I have a 2105 model. When I turned the key I got a single click. Lights all work and radio. I got a code P0004 from my OBD2 scanner. I got the car to start randomly luckily to read the code. Has any had this code with the 2105. How much trouble am I in? I just had the ac compressor changed and sparks plugs and coils and head gasket were changed too.