> Whilst a short can be of insufficient current to blow the fuse, but of
> sufficient current to cause a slightly dodgy connection between it and the
> voltage source to go open-circuit or almost so, if the problem were in the
> turn signal switch it would be there all the time and not just when you
> operate the brakes. If you have 12v on the hot side of the brake switch
> normally, but it drops to zero or nearly so when you operate the brakes,
> then there is either a short (or nearly so) on the brake lights plus a
weak
> connection between the switch and the battery, or simply a bad connection.
> If the brake lights work by connecting the lights side of the brake switch
> direct to the battery, without smoking your linking wire, then you can
> discount a short at the lights. Which leaves the bad connection. Do the
> turn signals and running lights work with the brakes on? If so, and if
the
> brake light switch gets its 12v supply from the turn switch as you imply,
> then the fault must be between the two switches. It could be where a wire
> joins to a connector or a connector to a component. If the turn signals
> fail as well then the problem lies between the turn switch and the
battery.
>
> PaulH.
But thinking on if the brakes and turn signals use the same wiring to the
back of the car and bulb filaments, and the turn signals work OK, and the
turn signal is of the type that pulses the brake light one side if the two
are used together, then that wiring and bulbs etc. must be OK, as must the
wiring etc. from the turn switch towards the battery. So any problem can
only be in the brake switch, its wiring to the turn switch, or the part of
the turn switch that controls the brake lights. Removing the connectors
from the brake switch and bridging them together eleminates the switch, and
bridging the connectors on the turn switch that the brake switch is wired to
eliminates that, leaving just the turn switch itself. As a guess, not
having a TD diagram.
> ----- Original Message -----
> From: "Roger Wilt" <rdwilt@pol.net>
> To: <mgs@autox.team.net>
> Sent: Thursday, August 19, 2004 3:05 AM
> Subject: TD brake light saga better but continued
>
>
> > Well, I found out the brake hydraulic switch was going bad but not
> > completely bad... yet. Got a new Moss switch anyway - still no brake
> lights.
> > Was able to determine that everything works fine until I hook up the
brake
> > switch wire which goes to the turn signal box (a lever action "ALLSTATE"
> > brand). then lost current across switch when brakes engaged. Took apart
> the
> > turn signal box, disconnected the brake switch wire, and ran a new wire
> from
> > the cold contact on the brake switch to the rear wire turn signal, hit
the
> > brakes and a brake light lit up!!!
> >
> > My current theory is there is a short circuit to ground in the turn
signal
> > switch but somehow preserved running lights and turn signals. Whew! I'm
> > going to further dismantle the switch this weekend and hope for a cure.
If
> > not, I will be asking for direction on a new brake light / turn signal
> > switch / setup.
> >
> > Any other thoughts are appreciated.
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