Chosen Solution
Two months ago the system became sluggish, so I ran the hardware diagnostic tool and it gave the error 4SNS/1/C/0000008:TC0D–124. The battery was weak and would only run for 2 hours. A few days ago , it refused to turn on. The battery is dead as the battery indicator lights blink 5 times. The light on the magsafe when connected is green.
Here’s a good writeup on the AHT & Apple diag errors: Finding Hardware Faults: Exploring AHT & Apple Diagnostics Its a bit cryptic here’s what you have: 4SNS - System sensor /1/C/0000008: T - Temp C - CPU 0 - Optical drive D - DC Power These all roll up to a SMC issue with its sensors inputs. Did you have a liquid spill at some point? This will need some serious repairs! I would recommend you locate someone who has micro-soldering skills to fix your logic board.
