dead yellow tops
 

so i bought two yellow tops befor i left on deployment, from the time i left untill nov when i went on rnr my wife drove the truck once a week. after she got back to HI the batt were dead wouldnt even take a charge. ive had to replace the starter twice. i just bought on from the cummins shop on island. and the yellow tops were also replaced. my Q how could after 20 days of not runnin my batt get so low they wouldnt hold a charge, i was reading some of the older tech tips an found one about a 24v starting hard come to find out it was his seat retractor timer module caused by an 'overdraw' of current. would this also be a prob for our 12v? i know the 98 has the same seats as the 24v.