Hi Mark, As you look at the two filaments, the larger one (it's not wound as tightly) will light when you have your tail lights on. The smaller one is for your turn signals and brakes lights which is quite a bit brighter. The only time both filaments should be lit is when the tail lights are on and either brake or turnsignals are activated. If when you step on the brakes and the larger element lights ( and you don't have your parking lights on) there's either a ground problem or I've seen where someone has put in a single contact bulb in a double contact socket. Hope I haven't confused you too bad-I was always taught, electricity is lazy, it will take the easiest path to ground. Steve ----- Original Message ----- From: "Mark McDonald" <tomswift@xxxxxxxxxxxxx> To: <mailing-list@xxxxxxxxxxxxxxxx> Sent: Thursday, June 26, 2003 10:21 PM Subject: Re: IML: bulbs for '68 taillights > Steve, if they don't both light, what's the point of 2 filaments? Maybe I'm > missing something. What makes the taillights brighter when you apply the > brakes? > > If there is a problem, it is a problem that is duplicated on all my Imperials . > . . > > Thanks, MM > > Stevan Miner wrote: > > > Hi Mark, > > When you apply the brakes both filaments aren't supposed to light on those > > 1157's. I'm guessing that you have a bad ground somewhere and that is what's > > causing both to light. When you get that fixed you'll find that they are > > both brighter, taillights and brakelights. Try a 1156 bulb to replace those > > 1095's. > > Steve Miner > > Miner Auto Service > > Winnebago, MN 56098 > > >