Headlights won't go off

[Greg Young]

I ran a line from the buss and breaker board in front of the dashboard, down to relays mounted on the inside of the headlight housing. That line is fine. The relays only switch on when they have the trigger voltage, as they're supposed to.

I thought it easiest to put the relays near the headlights since the trigger lines (originally the power lines) were already there.

So why are the trigger lines showing voltage (thereby triggering the relays) when the switch is off and showing no voltage? And why suddenly, right after I turned on the headlight switch, when the bus hadn't been moved in two months?

Remember that the fluorescents in the living room would only come on randomly? I never have been able to fix that. We have electrical gremlins.

Greg

On Aug 18, 2010, at 7:20 PM, "Dan and Cindy" <"86bluebird@sbcglobal.net"> wrote:

Where did you pick up the 12V for the relays? The headlight switch is only the trigger.



--- In "WanderlodgeForum%40yahoogroups.com", Greg Young wrote:

>

> Hi Dan!

>

> There's definitely 12V getting to the relay from somewhere. However, I don't

> find any voltage at the switch. So it's getting it from somewhere else. I've

> tried to trace the control lines back from the relays, but there's so much

> spaghetti, and they're wrapped like most wires on the BB in a heavy black fabric

> casing. I'll keep trying.

>

> If I can't diagnose and fix this before the weekend, I may try pulling the

> headlight line off the circuit breaker when I stop. I'd be driving with

> headlights on in daytime, but nothing wrong with that. We have to be on the

> road by Monday first thing and have a lot of packing to do!

>

> Greg

>

> Each time you judge yourself you break your heart.

> -Kirpal Venanji

>

>

>

>

> ________________________________

> From: Dan and Cindy <86bluebird@...>

> To: "WanderlodgeForum%40yahoogroups.com"

> Sent: Wed, August 18, 2010 7:04:37 PM

> Subject: [WanderlodgeForum] Re: Headlights won't go off

>

>

> Greg

>

> If you turn off the headlight switch, you should be removing the 12V to the

> headlights. Pull the dash out a little and check to see if there is 12V going

> out when the switch is off. Worst case for now eliminate the 12V to the relays.

> Then try to troubleshoot how it is getting the 12V.

>

> --- In "WanderlodgeForum%40yahoogroups.com", Greg Young wrote:

> >

> > Hi folks -

> >

> > My headlights just won't turn off. This happened suddenly when I was testing

> >them as we are preparing for a trip. I switched on the lights, and they won't go

> >off.

> >

> >

> > I have the relay mod installed. And instead of one relay for low, one for high,

> >I have four relays - two each for each side (1 high, 1 low). Since both low

> >beams are on, it can't be just one of the relays. (though I did try replacing

> >one anyway to no avail)

> >

> > At first I thought it was the dashboard headlight switch, so I replaced that

> >but no change.

> >

> >

> > I'm pretty sure that somehow I've got a short on the wire from the dash switch

> >to the relay, but I don't see any problems and can't figure out why it would be

> >triggered by turning on the headlight switch.

> >

> >

> > Any thoughts very much appreciated. I'm about ready to call in a pro on this

> >one.

> >

> >

> > Greg Young

> > 1986 PT40 Bluefire

> > Oceanside CA

> > >

> >

>