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TR2/3/3A TR3 Tail Light Wiring Question

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mountainman

mountainman

Jedi Trainee
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Does the tail, front and rear turn signal, lic plate, and head lights get their ground from the mounting plates or do I run a ground wire from each one to the body? Also should I put an in-line fuse on each circuit?
Thanks
Greg
 
The headlights and front turn signals had their own ground wires from the factory, which come up to ground clips to the rear of the horns.

The rear lamps were originally grounded through their mounting screws; but I feel it's a worthwhile upgrade to add separate ground wires for them. I made up a black wire with bullets for each lamp, and a ring terminal for one of the gas tank bolts.

The turn signals & brake lights are already fused, no need for more, IMO. The factory added an in-line fuse for the tail lights at some point (TS39781LO had it) which would be a worthwhile addition to cars that don't have it.

If you want to add fuses for the headlights, it's probably best to use a separate fuse for each filament, so that a single fuse failure doesn't suddenly cause both headlights to go out at an inopportune moment. I only had one fuse for both high beams on TS39781LO, and it failed while I was descending a mountain at rather high speed on a dark night. Of course all I had to do was find and hit the dimmer switch, but it was still a rather scary moment.
 
I believe the in-line fuse Randall mentioned is behind the center instrument panel (I mention that in case you're looking for it in the boot) and also protected the instrument lights. I added it to mine (TS47905L) though I don't know whether it was there originally and lost thru the years or never there at all.

An alternative to fusing the headlamps might be to add a fusible link at the main power feed coming off the solenoid. I added that (at the suggestion of posts here) for some last-ditch protection. An archive search will likely turn up more info on 'fusible link'.
 
Geo Hahn said:
I believe the in-line fuse Randall mentioned is behind the center instrument panel (I mention that in case you're looking for it in the boot) and also protected the instrument lights.
Click to expand...
Right. A metal holder, clipped to the bottom edge of the dash just below the instrument panel (right where it used to snag my glove when shifting into 3rd gear). It protected all the lamps controlled by the first position of the headlight switch, including panel lights & front marker lights. Here's a wiring diagram that shows the fuse (item 41).
https://i258.photobucket.com/albums/hh260/TR3driver/TR3ALHDSCHEMATICMODIFIEDFROMPRAC-1.jpg
 
And as long as your doing it right, change the turn signal holders to the same as the front turn lamps.This allows you to then add a wire from the stop lamp to the inner bulb and have 4 brake lamps without messing up your turn signals.This safety modification will NOT get you a deduction at concourse, but it may save your life!!Remember a whole generation of childeren has grown up with third brake lamps in every cars rear window!!!
MD(mad dog)
 
MDCanaday said:
And as long as your doing it right, change the turn signal holders to the same as the front turn lamps.This allows you to then add a wire from the stop lamp to the inner bulb and have 4 brake lamps without messing up your turn signals.
Click to expand...
I did that to TS39781LO ... but the guy who rear-ended me was simply not watching where he was going :nopity:

Note that for this approach to work legally, you have to use the low power filament for the brake lights (so the turn signals can still be seen when the brake lights are on).

For TS13571L (which originally only had a center brake light), I took a different approach and added a pair of relays & resistors so that the bright filaments could serve double duty as both brake and turn filaments. It also removes the load from the original brake light switch, which I'm hoping will extend it's life.
 
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