vintage 1985 is just when Dometic came out with the AES model refers. AES stands for Auto Energy Select. They had a an ON /OFF switch with an indicator light. MANUAL Dometic Models, you had to HOLD the Pilot button and then continually push a Manual Piezo lighter button. If the OP has just an ON OFF switch, then he has an AES and requires a 12 volt source to operate. If he has to push in a button and then continually push the LIGHTER button, he does not need a 12 volt source. AS always, MODEL is required to correctly answer his question. Doug
