Jeep Repair: jeep repair, jeep cherokee classic, jeep repair

Question
I have a 98 Jeep Cherokee classic. The problem is the other day when i went to start it the battery was dead. I have taken it to the garage and they are telling me it not the battery or alternator. that it might be in the security system.  could you give me some idea what you think it could be or suggestions

thank-you

Answer
replace the battery   if u drove it to the shop  U know the alternator is good  and well they never go out on Chrysler products any way. If its a security system  it will be a different kinda no stat    what happens when u turn the key over??  and lights   headlights bright?