Bob,
Did you measure 12V coming out of the switch with the wire going to the
light disconnected? If so, what does it measure with the lights connected
and the pedal pressed? Have you tried connecting together the two wires that
go to the switch? If that turns the lights on, I'd guess that the switch is
bad. If the switch contacts are bad (have a high resistance) it will limit
the current to the brake lights.
Sometimes you can give a switch a good spray of WD 40 to fix something like
this.
- Hugh
> -----Original Message-----
> From: owner-triumphs@autox.team.net
> [mailto:owner-triumphs@autox.team.net]On Behalf Of Nancy and Bob Wise
> Sent: Saturday, August 31, 2002 4:23 PM
> To: triumphs@autox.team.net
> Subject: totally confused (TR3)
>
>
> The brake lights on my 1961 TR3A do not work, and I am out of ideas.
>
> I have 12V going to the brake light switch (on frame, under carbs)
> via a green wire that comes directly from the
> ignition-switch-controlled side of the fuse box. When my lovely
> assistant steps on the brake pedal (with ignition switch on) I get 12
> V out of the brake light switch via the purple-on-green (P/G) wire
> that leaves the switch. When I jump directly from the battery to the
> P/G wire that goes from the engine compartment to the brake lights,
> the brake lights come on. When I connect the green wire that comes
> from the ignition-switch-controlled side of the fuse box directly to
> the P/G that goes to the brakes (i.e. bypass the brake light switch
> completely), the brake lights come on.
>
> HOWEVER, when I connect the 12 V P/G/ wire leaving the brake light
> switch to the P/G wire that goes to the brake lights (i.e., the
> normal wiring setup), I have no brake lights. I have sanded all
> connections and replaced the in-line connectors (under the carbs). I
> have even held the two wires (P/G leaving brake light switch with 12
> V to P/G going to brake lights) in direct contact, and still no brake
> lights.
>
> So:
>
> a) the pedal-activated brake light switch works
> b) the lamps in the brake light fixtures work
> c) but the lamps only come on with the 12V from the battery (or fuse
> box) and not with the 12V from the brake light switch.
>
> Is it an amperage problem? Is the brake light switch giving me 12V
> but very low amps? How do I test that? Am I forgetting something
> that is incredibly obvious? Why does Joseph Lucas hate me?
> --
> Bob and Nancy
/// triumphs@autox.team.net mailing list
/// or try http://www.team.net/cgi-bin/majorcool
/// Archives at http://www.team.net/archive
|