I swapped out the interior bulbs in my '92 K2500 for LEDs so that I don't use so much battery power with the doors opened. Two of the bulbs are 1156 replacements and the dome (overhead) light is a 211-2 type.
When I put in the LED dome bulb, it works as it should with the doors open, but continues to glow very dimly with the doors shut. I put my meter on the light fixture and found about 6 volts at .01 microamps. I know thats not much, but it is enough to barely light the LEDs. Do I have a problem somewhere? Maybe a bad ground?
I put my ohm meter across the LED bulb and it shows open, while the standard incandescent bulb shows about 1 ohm.
Does it beg the question, if the volts are sitting there, not being used by an incandescent that they cant light up, do they not drain the battery.... but a low power LED that actually lights up will?
I dig science
[This message has been edited by 2.5 (edited 05-23-2018).]
Does it beg the question, if the volts are sitting there, not being used by an incandescent that they cant light up, do they not drain the battery.... but a low power LED that actually lights up will?
I dig science
I would think that the very low resistance (essentially a short) of the incandescent bulb would drain the battery faster than the (almost) open LED. I think that the very low (.01 microamp) current just drains so slowly that it would take weeks to make a difference. But there should be no voltage there when the doors are shut. I would have never even known about it if I hadn't tried to install the LED.
Actually, I'm kind of surprised that such a low current will light the LEDs.
[This message has been edited by williegoat (edited 05-23-2018).]
Have you changed other bulbs to LED? maybe there is a sort of conflict somewhere for lack of a better word.
The only bulbs I have changed to LED are the three interior lights mentioned in my first post and the one under the hood that lights when I open it. The purpose was to be able to leave the doors or hood open without worrying about battery drain. LEDs use much less current than conventional bulbs.
Yes, LEDs will light for low volts that normal bulbs doesn't even begin to glow.
2 possible items... If only switches are used for on/off then switches can be going bad or dirty. If BCM etc is controlling them then may use transistors/MOSFET and leak some volts often as part of monitoring for bad bulbs... the famous "CAN BUS errors." The resistor here likely does same as LED saying doesn't cause the can bus problems.
Just read lighting circuits in haynes etc books. First issue should be fix not a band-aid to hind. Second is annoying but isn't a problem to the car in most cases.
0.01ma added to whatever ECM/PCM and Radio standby power will drain the battery but takes weeks at normal temps. If parked for winter then anything draining the battery can make battery to freeze very easy. Freezing battery will kill then even if load didn't drain it more then 1-2 volt low.
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
Yes, LEDs will light for low volts that normal bulbs doesn't even begin to glow.
2 possible items... If only switches are used for on/off then switches can be going bad or dirty. If BCM etc is controlling them then may use transistors/MOSFET and leak some volts often as part of monitoring for bad bulbs... the famous "CAN BUS errors." The resistor here likely does same as LED saying doesn't cause the can bus problems.
Just read lighting circuits in haynes etc books. First issue should be fix not a band-aid to hind. Second is annoying but isn't a problem to the car in most cases.
0.01ma added to whatever ECM/PCM and Radio standby power will drain the battery but takes weeks at normal temps. If parked for winter then anything draining the battery can make battery to freeze very easy. Freezing battery will kill then even if load didn't drain it more then 1-2 volt low.
There is no CAN bus. The only computer is the ECM. The technology in this pickup is essentially the same as that of the Fiero.
After following through on LightbulbwithaFiero's post, I have learned that LEDs can glow with extremely little current. I am actually talking about .01μA, not mA. This can be generated by adjacent wiring through capacitance. There is constant power to the fixture because it also includes two map lights. In one video, it was demonstrated that the LEDs could be made to glow by cupping one's hands around an LED board which was mounted in a socket with only one wire attached to the power source.
Bear in mind that the glow in my dome light is so dim that it cannot be seen, once the white plastic lens is in place.
Silly question, but how are the stray EMF fields around you parking spot ? Wires or cell phone towers ?
IE: A fluorescent tube can be lit just by picking up stray fields from high tension wires. (There are a bunch of videos on YouTube of it)
Could be something similar going on.
10 years ago I was playing around building cell phone chargers that worked by picking up stray fields from CRT monitors instead of plugging into the wall. It was more of a trickle charger and then those wireless charging pads came out so that killed that idea.
[This message has been edited by MidEngineManiac (edited 05-24-2018).]
I have noticed that it will stop glowing after a few hours, but as soon as I open a door it starts again. It will go out immediately if I disconnect the battery. The battery still has plenty of juice after sitting like this for a few days, so I guess I won't worry about it.
I blame the Russians......or maybe the space people.......or maybe Russian space people.
[This message has been edited by williegoat (edited 05-24-2018).]
If you manually turn off the dome lights with the switch on dash, do they go out ? I know my Dodge Caravan has the auto dome normal lights that turn off after like 10 mins. They do that but ive found if I leave the sliding door open there is still a drain that kills the battery in a week even though the lights are out. If I shut the doors, it stays charged for at least a month. I think something in the computer that turns them off with a delay is defective. If I turn off the manual switch on dash, the battery is fine with the doors open or closed. Someone suggested the little 'door ajar' lite in panel is draining it.
I switched all the interior and porch lights on one of my RVs to LEDs and dont have any problems. I leave the porch lights on for weeks/months without running the batteries down. I occasionally, like once a month plug it into the garage so the converter charges them to full. The outside lights are a crime deterrent.
[This message has been edited by rogergarrison (edited 05-28-2018).]