Battery Charging
 

I have a 2003 Yamaha Electric golf car. Recently, the charger stops charging and 2 red lights begin to blink, indicating an abnormal charging cycle. Two of the batteries feel warm to the touch. The batteries are 2 1/2 yrs old and bought from Battery Boys, their brand. Any suggestions as to what is happening here? A friend mentioned that it may be a circuit board in the charger.

I would not blame the charger yet, the fact that two batteries are warm could mean that one or more cells in the battery pack are shorted causing the charger fault.
If the charger is unable to reach its designed goal of charging the system it will show a fault.