View Full Version : TR2/3/3A TR3 Taillight problem

05-30-2005, 12:20 AM
When I turn on my ignition my taillights come on. This started to happen about a month ago and now it happens all the time. When I turn on the light switch the taillights stay on and the headlights come on. What are the most common problems here? You guys have saved me a lot of time in the past, so I thought I would try again. Thanks ....AL

05-30-2005, 01:11 PM
Are you sure that it is your tail lights and not your brake lights. I had my brake switch sticking in the on position some of the time until it final stuck in the off position.

Geo Hahn
05-30-2005, 05:39 PM
I'll bet Don's got it. The way the switches are wired (with the 'side/head' switch always powered) it would take a major fubar to have the tailights come on with the ignition on and 'side/head' switch off.

Paul Johnson
05-31-2005, 08:59 AM
You could also have what is known as a crossover circuit. If the brake light switch is stuck (hydraulic) or maladjusted (mechanical), the brake lights would be on whenever the key is on, and if there's a crossover, so would the tail, side and dash lights. Do the parking (side) lights also come on? Is there any possibility that you have a single element bulb in one of the sockets? Try removing all four (tail, side) bulbs one at a time and see if the issue goes away. You could have a crossover in bulbs, holders, or any wiring. Another good way to check this is to see if the dash lights also come one. If so, then you certainly have a crossover.

05-31-2005, 09:36 AM

You were right on ...it was the brake lights. I adjusted the switch on the brake pedal and that solved the delima. Thanks again...this forum is GREAT!

Geo Hahn
05-31-2005, 01:55 PM
...I adjusted the switch on the brake pedal...

[/ QUOTE ]

I assume you know that TR3s brake lights were originally operated by a hydraulic switch located at the 5-way connector that is on the frame down below the carbs. Your original switch may still be there if only to plug the hole in the connector. The originals rarely failed I think (not so the replacments) but could get gunked up.

If you're happy with the mechanical substitution that's fine -- just thought you might want to know.

06-01-2005, 12:59 AM

Yes, I have the pressure switch, but it was not connected when I got the car (3 years ago), so I "assumed" that there was something wrong with it and the previous owner installed the mechanical pedal switch. Thanks for your input. Just for the heck of it one day I will reconnect the prssure switch and see what happens. Thanks ...........AL