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-   -   LED Doesnt Work Incandescent Does (https://67-72chevytrucks.com/vboard/showthread.php?t=764626)

The Rocknrod 05-28-2018 05:16 PM

LED Doesnt Work Incandescent Does
 
Anyone else have any experience with an LED light bulb not working and a incandescent bulb working in the same socket?
I have a AAW courtesy light kit I installed recently that works fine if I use a regular bulb but not if I use a recently purchased LED bulb.
https://i.ebayimg.com/images/g/BzUAA...DO7/s-l500.jpg
https://5fc98fa113f6897cea53-06dfa63...jpg?1429821530
https://i.ebayimg.com/images/g/spQAA...qf/s-l1600.jpg

The Rocknrod 05-29-2018 01:31 AM

Re: LED Doesnt Work Incandescent Does
 
1 Attachment(s)
Yes I checked, shown here.

phat69 05-30-2018 11:35 PM

Re: LED Doesnt Work Incandescent Does
 
Install the bulb and see if the base shows +12v with a tester. The shoulder on the base may be interfering with the socket and not allowing contact at the bottom.

Dead Parrot 06-01-2018 01:14 PM

Re: LED Doesnt Work Incandescent Does
 
Double check that the polarity of the wiring you are connecting your kit to matches what the kit wants. Possible a PO made some modifications.

Are the LED bulbs even polarity sensitive? Some are some aren't. Don't want to be chasing a polarity problem if the bulbs don't care.

Could be the circuit you are getting power from wants a certain current draw to go active. The old style turn signal blinker for example. Don't know why a courtesy light circuit would care but stranger things have happened.

The Rocknrod 06-01-2018 01:34 PM

Re: LED Doesnt Work Incandescent Does
 
Polarity of the wiring is good.
I plugged in an incandescent it works.
See post #3 again, thats the LED bulb, the Incandescent was done the same way. It works both in the plug and on the bench the same as the LED bulb.
I tried 3 LED bulbs (from the same seller though).

DLW 06-01-2018 02:34 PM

Re: LED Doesnt Work Incandescent Does
 
Only thing I can really think of is if for some reason the the nubs on the side of LED are not contacting the ground wire after twisting them in. Is the side nubs shorter or anything different? You could try to just use a test wire from bulb body to ground while in the socket to see. I would just start troubleshooting like that, do the same for power if ground is ok.

Robznob11 06-03-2018 12:18 AM

Re: LED Doesnt Work Incandescent Does
 
Quote:

Originally Posted by The Rocknrod (Post 8272809)
Polarity of the wiring is good.
I plugged in an incandescent it works.
See post #3 again, thats the LED bulb, the Incandescent was done the same way. It works both in the plug and on the bench the same as the LED bulb.
I tried 3 LED bulbs (from the same seller though).

Just checking....you do know that a regular bulb will light up either way the wires are hooked. (Not polarity sensitive) just because it lights with the wires the same direction as the led ....does not mean the polarity is correct. The quickest and easiest test is to reverse the wires on the socket. If that does not work check it is making good connection on the ground. Only other thing to check is if you have a true 12+volts. A regular bulb will light with very little current , many leds will not. They are built for a specific voltage/current flow.

The Rocknrod 06-08-2018 12:53 PM

Re: LED Doesnt Work Incandescent Does
 
Quote:

Originally Posted by Robznob11 (Post 8273827)
Just checking....you do know that a regular bulb will light up either way the wires are hooked. (Not polarity sensitive) just because it lights with the wires the same direction as the led ....does not mean the polarity is correct. The quickest and easiest test is to reverse the wires on the socket. If that does not work check it is making good connection on the ground. Only other thing to check is if you have a true 12+volts. A regular bulb will light with very little current , many leds will not. They are built for a specific voltage/current flow.

The same voltage shown in post #3 is used on the sockets in the truck, thats an LED being lit in post #3 with the same power used on the truck to light an incandescent. Also I bumped up the amps on the truck just to make sure.
I checked polarity from the socket + and - to the fuse/ground panel. It's dead on, ground to ground, power to power, not switched there. I'm stumped. All I can think of is the little tabs arent making contact well enough in the American Autowire socket on the LED bulbs from China. Not that you can even buy them made in America so thats a mute argument.

DLW 06-08-2018 03:50 PM

Re: LED Doesnt Work Incandescent Does
 
As I said in my other post, there is only power and ground, it's not getting one of them while plugged into the socket it seems. You can simply take a separate wire and run it from a good ground, to the bulb body (while LED is in the socket) to test the tab being to short or mis-aligned to contact the white wire tab theory. If it lights up its the ground issue. I just got a similar setup from Ron Francis the other day, doubt I use LED's, but I think I have a couple I can try out.

Robznob11 06-08-2018 03:52 PM

Re: LED Doesnt Work Incandescent Does
 
Quote:

Originally Posted by The Rocknrod (Post 8277388)
The same voltage shown in post #3 is used on the sockets in the truck, thats an LED being lit in post #3 with the same power used on the truck to light an incandescent. Also I bumped up the amps on the truck just to make sure.
I checked polarity from the socket + and - to the fuse/ground panel. It's dead on, ground to ground, power to power, not switched there. I'm stumped. All I can think of is the little tabs arent making contact well enough in the American Autowire socket on the LED bulbs from China. Not that you can even buy them made in America so thats a mute argument.

You say you bumped the amps up on the truck???? Is the battery dead? Are you testing with a dead battery and charger on it? The only reason I ask is because I had a fellow say his led tails would not light. Come to find out his battery was low so he attempted to check them in the truck and use a battery charger for a little boost. The problem is there is a significant voltage drop in the wiring...especially if it is stock. Leds are also voltage sensitive too. Meaning they need close to full voltage to light. It sounds crazy but I saw first hand ....with a new battery they worked perfect. With that said some leds are more forgiving than others. The square superflux I use now will light with 1/2 to 3/4 voltage. The little cheap 2 leg ones usually do not.

The Rocknrod 06-08-2018 05:32 PM

Re: LED Doesnt Work Incandescent Does
 
I'm going to use the wire idea from the ground to ground.
I have other LED's light up on the truck, Cab light etc. Suffice it say I'm not using a "battery".
Let you know on the wire.

Robznob11 06-08-2018 06:30 PM

Re: LED Doesnt Work Incandescent Does
 
Looking at the plastic housing and bulb you are using. It really can only be 3 things...
1. Prong in middle is not contacting prong on bulb.
2. You are not getting a good ground to the housing of bulb.
3. You have the wires backwards.
Your bench test eliminates everything else!

toolboxchev 06-10-2018 06:41 PM

Re: LED Doesnt Work Incandescent Does
 
and the top rated cause of LED lighting not working is wiring is backwards. This applies specifically to DC voltage systems.

Ramjet51 06-12-2018 09:03 PM

Re: LED Doesnt Work Incandescent Does
 
Ok Master Chief...I note that you’ve got alligator clips during bench test...so if you’ve got power on the wires, I agree with others, it’s the metal housings that’s the issue. Eliminate them at the end of the wire .... run with temporary clips...it’s got to be simple..EMC(SS)...

Ramjet51 06-12-2018 09:09 PM

Re: LED Doesnt Work Incandescent Does
 
Ok Master Chief...I note that you’ve got alligator clips during bench test...so if you’ve got power on the wires, I agree with others, it’s the metal housings that’s the issue. Eliminate them at the end of the wire .... run with temporary clips...it’s got to be simple..EMC(SS)...

The Rocknrod 06-13-2018 06:42 AM

Re: LED Doesnt Work Incandescent Does
 
Well I'm in Ohio right now so I will be home in a month and figure this out. Thank you for all your help on this. I will check the 'wires backwards' thought on this right away when I get home. It could happen. :)

DLW 06-13-2018 08:51 AM

Re: LED Doesnt Work Incandescent Does
 
If the regular bulb works fine as you said, it is not wired backwards :)..

From your test, you know power is bottom, ground is body on both bulbs, and the AA courtesy light kit is wired the same way.

LED just is not getting power or ground from the socket, or, as was mentioned, insufficient voltage for LED, which I only bring up because you mentioned you are not using a battery so I assume you are using a battery charger for all this and that is what the alligator clips are? Just an idea there.

Robznob11 06-13-2018 09:14 AM

Re: LED Doesnt Work Incandescent Does
 
Quote:

Originally Posted by DLW (Post 8280441)
If the regular bulb works fine as you said, it is not wired backwards :)..

From your test, you know power is bottom, ground is body on both bulbs, and the AA courtesy light kit is wired the same way.

LED just is not getting power or ground from the socket, or, as was mentioned, insufficient voltage for LED, which I only bring up because you mentioned you are not using a battery so I assume you are using a battery charger for all this and that is what the alligator clips are? Just an idea there.

Ummmm... this is wrong information....the regular bulb does not care which way the wires are...it will light if you swap it either way. Now if it was a stock housing on a single pole bulb it would be safe to assume that they were correct because if they weren't there would be a short since most stock housing ground to the body some how. But since it is a plastic housing with wires...someone could easily swap them wrong. Everyone said check polarity in the first few post. This did not mean polarity of the bulb it ment polarity of the socket. That is what matters. There is no polarity on a regular bulb!

DLW 06-13-2018 03:40 PM

Re: LED Doesnt Work Incandescent Does
 
I hate putting wrong information, you are definitely correct, thanks for correcting, my bad. You would think I would know better after just rewiring my whole truck.

I guess what I should of said is if the orange wire is ran to power and white is to ground as it should be (it's written right on the wire), then it is not backwards :)..

GOPAPA 06-13-2018 04:54 PM

Re: LED Doesnt Work Incandescent Does
 
They make flashers for Led and flashers for incandescent. if not mentioned above ..this may be the problem

Robznob11 06-13-2018 05:05 PM

Re: LED Doesnt Work Incandescent Does
 
Quote:

Originally Posted by GOPAPA (Post 8280725)
They make flashers for Led and flashers for incandescent. if not mentioned above ..this may be the problem

You are correct but those are for blinkers and flashers. Probably not for a courtesy light. But while we are on the subject ....those are polarity sensitive as well and many may find they need to reverse the wires on those as well for them to work. It just depends on the flasher you buy....I had to on my turn signal side using an EZ wiring kit...


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