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Heres one for you electrical gurus.....

koosh

koosh

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Bought LED dome lamp, much reduced heat, and brighter. But when closing the doors....the light stays on!!!
Put original bulb back in, light goes off every time doors close.....this is beyond my comprehension!!!!
 
Possibly leakage through the door switches, or a bad ground. LED's require very little excitation voltage to get them running. The Incandescent style lamp (original bulb) has enough resistance to pull down the few volts that are bleeding out through bad switches, and thus give the impression they are completely 'off'.

That is just my opinion anyway. :)
 
It has something to do with the wiring. I remember there was someone somewhere that changed out their tail/stop/turn sigs with LED's, and had nothing but a boatload of problems. They wound up having to rewire the back section to make it work. Sorry I can't offer more help. Good Luck
 
Ground or neg probably isn't breaking completely with the door closed. Like kiwi says, the led doesn't need much of a connection to make a circuit, whereas an incandescent bulb needs a solid connection. This is why bad ground connections cause dim headlights etc. Remember the dome light has power to it all of the time and gets grounded through the door switch . A small resistor connected to the neg wire in the dome light might fix it.
 
I may just try changing out the jamb switches, they r cheap enough to try, thanks
 
If the light is bleeding to ground your battery will die after awhile
Look for leak
 
bm02tj said:
If the light is bleeding to ground your battery will die after awhile
Look for leak
Click to expand...
I put the old bulb back in, so light is going off.....not sure how to look for this "leak".....
Also, why is there a double contact bulb in a dome light?
 
U guys r goooooood
 
take wires off the switches then ground the wire to the body if it goes out correctly then the switch is bad. if it continues to stay on your looking at a problem in the socket or to the switch. hope this make sense
 

The 1004 bulb used for the dome lamp fixture is a double contact single filament bulb. The bulb socket sleeve is not electrically part of the circuit, only the two contacts. Are you sure the LED replacement is configured the same way?
 
Glenwood said:
Ground or neg probably isn't breaking completely with the door closed. Like kiwi says, the led doesn't need much of a connection to make a circuit, whereas an incandescent bulb needs a solid connection. This is why bad ground connections cause dim headlights etc. Remember the dome light has power to it all of the time and gets grounded through the door switch . A small resistor connected to the neg wire in the dome light might fix it.
Click to expand...

If the LED assy just connects to 12v, it already has an internal resistor to limit current thru it, which is the most likely case. Most LED's can only handle about 100mA to about 500mA depending on color (internal material). LED's (a diode) will forward bias (operate) at 0.7v, and the light intensity will get brighter as voltage increases until it burns out the junction due to too much current. If there is enough leakage in a bad switch, it could be enough to forward bias the LED whereas an incandescent bulb would require a couple of volts to produce usable light.
 
Take the LED bulb and ground the socket then apply power to one terminal at a time to see if it lights up
then ground one terminal and apply power to light up then remove the ground on terminal and see if it goes out
 
69Bee said:
If the LED assy just connects to 12v, it already has an internal resistor to limit current thru it, which is the most likely case. Most LED's can only handle about 100mA to about 500mA depending on color (internal material). LED's (a diode) will forward bias (operate) at 0.7v, and the light intensity will get brighter as voltage increases until it burns out the junction due to too much current. If there is enough leakage in a bad switch, it could be enough to forward bias the LED whereas an incandescent bulb would require a couple of volts to produce usable light.
Click to expand...


We used to have this issue with LEDs on an Allen Bradley PLC5 triac output card with LED indicators. The maintenance electricians would keep a light bulb/pigtail inside the control panel to test the outputs. The output card LEDs would light even if the output wasn't turned on due to leakage current.
I wonder if the OP's LED lamp could be in backwards?
 
Last edited:
72RoadrunnerGTX said:

The 1004 bulb used for the dome lamp fixture is a double contact single filament bulb. The bulb socket sleeve is not electrically part of the circuit, only the two contacts. Are you sure the LED replacement is configured the same way?
Click to expand...


I bet this is your problem.
 
Glenwood said:
We used to have this issue with LEDs on an Allen Bradley PLC5 triac output card with LED indicators. The maintenance electricians would keep a light bulb/pigtail inside the control panel to test the outputs. The output card LEDs would light even if the output wasn't turned on due to leakage current.
I wonder if the OP's LED lamp could be in backwards?
Click to expand...

Shouldn't work as the LED will not be forward biased hooked in reverse.
 
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