Steve, Thanks, yes, that is what I meant: when you have the taillights on and you depress the brake pedal, both filaments light up. Perhaps I wasn't clear. If you are just driving in the daytime, with taillights off, then no, both don't light up. The problem I'm talking about occurs only when you have the taillights on. Thanks again, Mark Stevan Miner wrote: > 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