the ev100 card is the brand and model nomenclature for the GE traction logic and semiconductor oscillation control card, which is mounted pretty far back up in this unit and not to be messed with unless you have had considerable training in the related safety issues of working on one of these controls. I would not be the least bit concerned, at this point, about "dry" solder joints, These cards are about 100 times more likely to have a connecting wire die of old age and vibration rather then the solders internal to the card to cause a problem
Are you waiting 8 hours after the charge cycle stops before operation of the truck? this is a 'must do'.
You may be able to set your charger to not charge quite so hot, rather than readjust the truck.