interior light question

[Rxsep]

I just replaced my interior light bulb to LED on my 84 targa. Much brighter than before however, the 3 position light stays lit but very dim when positioned in the position for automatic door. turns off normally manually. is this a faulty bulb or are LED interior bulb not going to be an option?

[Jack Stands]

I’d imagine you might have a weak ground in the wiring allowing some electrical voltage to still activate the leds. I replaced mine with a led (in my 914-6) and it works fine (even though the bulb does get warm). The interior light always has a 12 volt supply, and ground wires complete the circuit when the light is in the constant on or switched on position. Perhaps cleaning the door switch may solve your problem?

[ossiblue]

Originally Posted by Rxsep

I just replaced my interior light bulb to LED on my 84 targa. Much brighter than before however, the 3 position light stays lit but very dim when positioned in the position for automatic door. turns off normally manually. is this a faulty bulb or are LED interior bulb not going to be an option?

Only a guess based on what I've read about leds. The led bulb has a much lower resistance that incandescents. The bulb is always connected to current in the light fixture, and only the ground connection will cause current to flow. In the door switch position, that ground is through the wire to the door switches, in the OFF position, there is no mechanical connection in the fixture to a ground source.

It may be that you have a very slight grounding of the circuit from your door switches to the fixture, causing a very weak current flow--too low to overcome the resistance of an incandescent bulb, but enough to illuminate a led. Only a guess, but I know some have had some issues with led brake bulbs that require an addition of a resistor to make things work correctly.

Edit: Jack Stands posted as I typed, so sorry for the duplication.

[Rxsep]

thank you for the inputs. I will check my door switch.

[HaroldMHedge]

Recently I had a short in the interior light which caused the lights and ignition buzzer to come on intermittently. Dirt and dust had built up on the switch. Cleaning the switch with plastic safe contact cleaner fixed the problem.

[PeteKz]

I just replaced the interior light bulbs in my 1973 T with LEDs. Works great. More light, less heat, less current draw. It also helps greatly that the LED emit light only on one side, instead of wasting light up into the roof frame. I also replaced the trunk light and glove box light with LEDs. Much better.