[TR] TR3 brake light switch test

[Randall]

> Do the ones mounted 
> vertically do something?

Nope, just spares for the "horizontal" ones.

One "horizontal" fuse is only for the horns.  The other one is for nearly
everything that only works with the ignition switch on (except the ignition
coil itself and the generator warning lamp on the dash).  That includes the
brake lights.

If you look at the fuse block, it has 5 terminals with wires.  4 of the
terminals are at the ends of the "horizontal" fuses, while the 5th terminal
is off to the side.  The fuse next to the 5th terminal is the one for the
brake lights, wipers, heater, turn signals, and fuel gauge.

BTW, there is also a jumper hidden under all those wires, that connects the
5th terminal to the 4th terminal.  It can break.

Also BTW, depending on the vintage of your TR3, there may be another fuse
located in an in-line holder, clipped to the bottom edge of the dash (above
the gear shift and behind the dash).  If so, it controls the dash lights and
rear tail lights (not the brake lights).  I believe Bill Piggott wrote that
it came in around TS42000, only for US-spec cars; but TS39781LO had it (and
it looked original).

As long as we are talking about fuses, be aware that the old Lucas fuses
used a different rating system than modern American fuses do.  If you want
to use American fuses, an AGC 20 or SFE 20 makes an adequate substitute for
the 35 and/or 50 amps fuses specified in the Triumph documentation.  A 35 or
50 amp American fuse won't protect the wires.

Randall