2013 sportsman 500 ho Replaced battery and charged - starts and runs but the battery indicator flashes and cant get the taillights to work bulbs are good any help would appreciated

 

Battery indicator flashing is warning you that something is wrong with the battery,a connection issue or charging issue either from the regulator or possible stator short.Check all battery and ground connections first along with the regulator connections. Crank it up and check that you're charging 14-14.5 volts at the battery. If it's lower or just shows battery voltage most times it's a faulty regulator. You can eliminate a stator as the cause by checking resisitance between each yellow stator wire leading to the regulator. Should be a small amount of resistance between each wire with no wire shorting to ground.Also an ac output test can show if the stator is ok. This video shows how to test the stator. If the stator checks out you can go oem on the regulator or take a chance on a cheaper after market regulator.4012192 is the oem part number.https://www.ebay.com/sch/4012192%20Polaris?rmvSB=true