Chosen Solution
The fan only spins when I hold the power button for 10secs and connect MagSafe while holding the power button for another 10secs. Have done NRAM and SMC reset, nothing happens. MagSafe shows an orange light.
Lets try this, follow this guide MacBook Pro 13" Retina Display Early 2015 Battery Replacement just disconnecting the battery following the Steps to Step 6. Now set the system on its side so you can gain access to the keyboard with the battery connection not shorting. With the battery and any thing else disconnected press the power button a good 10 seconds so you fully discharge the circuit. Now plug in the MagSafe did the system spontaneously restart? If it did you need a new battery!