Changed battery now having issues

Hi , Changed the battery on the 4s , screen loads up fine, battery shows up as 100% but would not connect to wifi and would restart after every 5 mins , tried lots of the fixes i saw online tried changing date but it goes a bit crazy and flys way past what i need (like 2038) and then crashes , tried aeroplane mode no joy.

Thought it could have been the pressure contact so soaked that in alcohol and still n no joy , when connected to mac it won't let iTunes do a update the white apple just keeps flashing up , and when i just tried a complete restore to factory setting from dfu mode i got the unknown error code 4005 which has truly stumped me because if i put my old battery back in phone , wifi and everything else works perfectly

Hope someone can help

Many Thanks