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Topic Review (Newest First)
07-21-2007 07:59 PM
mcinfantry a bad ground will cause a leak.

also on military vehicles the indicator light on the turn signal arm will cause leak AND bleed.
06-28-2007 10:20 AM
cboy
Quote:
Originally Posted by Frisco
This could be where the problem is.
I'm thinking you might be right. I've bookmarked the item at Speedway and will order it up should the problem come back.
06-28-2007 10:18 AM
cboy
Quote:
Originally Posted by Bryan59EC
Dewey,
I noticed that you have a post about your cruise control. Might want to look into the vruise box as well. Amongst the fuse pulling---was the CC one of them??? Maybe that is what fixed it.
That's good thinking but I'm doubtful the two are related (although I wouldn't bet my life on it). The cruise went out last Wed. and I had the truck at Back to the 50's from Thurs-Sunday and no one noticed the bulbs being lit (and we spent a lot of time sitting behind the truck at the show). Also, the cruise was one of the first things I disconnected from the system when I started testing wires etc. In fact, when the bulb problem finally disappeared yesterday I immediately hooked the cruise wiring back up in the hopes it would either light the bulb...or even more hopefully solve the cruise malfunction. Unfortunately, neither happened. So I think I just had two totally separate gremlins hit at approximately the same time.

Actually, I think my cruise problem is a bad servo. I had it located about 4"-5" from the headers and I don't think it liked the heat. It's run without a hitch for 20K miles...but I think it finally gave up the ghost. I have a new unit on the way so when I install it (in a new and cooler location) I'll know for sure.
06-28-2007 07:29 AM
Frisco
Quote:
Originally Posted by cboy
I don't think so (is solid state on a chip board?)...but here are a couple pics. The hazard flasher is on the left and the turn signal unit on the right.
Go Here to read about turn signal flasher units for L.E.D. bulbs.

This could be where the problem is.
06-28-2007 06:49 AM
Bryan59EC Dewey,
I noticed that you have a post about your cruise control.

Might want to look into the vruise box as well.
Amongst the fuse pulling---was the CC one of them???
Maybe that is what fixed it.

just thinkin out loud here

Bryan
06-27-2007 08:53 PM
cboy
Quote:
Originally Posted by docvette
Measure the output side of the flasher with your meter and see if your voltage is there.
I'll try that in the event the problem returns. For the moment I'm just going to wait and see if the lights stay off permanently or if the gremlin returns.
06-27-2007 07:10 PM
docvette Doc here,

Nope, those are standard..

Measure the output side of the flasher with your meter and see if your voltage is there..A Standard flasher is Closed until enough current is drawn to heat up the tungston element, then it opens..

Doc
06-27-2007 06:41 PM
cboy
Quote:
Originally Posted by docvette
Are you using a Solid state Flasher unit?
I don't think so (is solid state on a chip board?)...but here are a couple pics. The hazard flasher is on the left and the turn signal unit on the right.
06-27-2007 06:30 PM
T-bucket23
Quote:
Originally Posted by cboy
Shoot. I HATE this. I solved the problem and I have no idea how I did it. I had all kinds of wires and fuses pulled apart trying to track down the stray voltage leak and never really determined for certain (much less fixed) where the problem was coming from. But I finally just decided to put everything back together (one step at a time) and as I did that the LED bulbs never came back on.

I'm still getting a very slight voltage reading at the wiring going to the array but apparently it is not enough to light the bulbs.

BTW, when I pulled the fuses for both the hazard/brake lights and the directional signal lights...I still got the stray voltage reading at the turn signals.

I'll be keeping an eye on it because it might just suddenly come back. Al least this time I think I have some good ideas how to go about searching for the problem.
I would be willing to bet it will be back, if it comes back try the disconnecting the turn signal switch.

When push comes to shove it probably isnt even something to worry about as the drain is proably so small it wont effect the battery at all.

I know if it was me I would still want to know why.
06-27-2007 06:02 PM
docvette Doc here,

Are you using a Solid state Flasher unit?

Doc
06-27-2007 05:54 PM
cboy Shoot. I HATE this. I solved the problem and I have no idea how I did it. I had all kinds of wires and fuses pulled apart trying to track down the stray voltage leak and never really determined for certain (much less fixed) where the problem was coming from. But I finally just decided to put everything back together (one step at a time) and as I did that the LED bulbs never came back on.

I'm still getting a very slight voltage reading at the wiring going to the array but apparently it is not enough to light the bulbs.

BTW, when I pulled the fuses for both the hazard/brake lights and the directional signal lights...I still got the stray voltage reading at the turn signals.

I'll be keeping an eye on it because it might just suddenly come back. Al least this time I think I have some good ideas how to go about searching for the problem.
06-27-2007 04:31 PM
Lonestar
Quote:
Originally Posted by T-bucket23
Good Points Doc
Something else to try is with the ignition off flip on the turn signals to one side and see if the other side goes out. If there is a capacitor on teh board that the leds are attached to if you disconnect the plug to the board, theoriginal light plug, the bulb should stay lit with no connection. Also unplug both lights and test with your meter for voltage at the wiring, if it is a real low current leak you may see the voltage go back up to 12 volts when you remove the load. You may also want to take the front bulbs out to test. The problem could be up front also. It takes a lot more current to light an 1157 than an led. Thats for sure.
Also if you disconnect the battery and the light go out you know its not a capacitor in the line. This should be a real simple test. Just remove the negative battery cable.
This will eliminate a lot of possibilities
He already stated that the LED's went out when he disconnected the battery.

I am with on the theory of a "leak", I wonder what happened when he pulled the turn signal fuse.

If you can identify by pulling fuses which circuit is causing the problem, then it may come down to disconnecting that circuit at various points starting at the tail lights and working your way forward. This should narrow the search down.

Now I am no electrical guru like Doc, but don't they make testers that can "sniff" out shorts and the like?
06-27-2007 04:10 PM
T-bucket23
Quote:
Originally Posted by docvette
Doc here,

An LED can possibly Run for weeks from the drain of an electrolytic Capacitor, provided the Cap was large enough..Like one of those OLD computer power supply caps, 1 MFD @ 100000 WVDC..(The ones that are so popular with Car Stereo Installers now..to keep high current drain stable on "Thump")

A Single LED would last for months on a fully charged cap of that type..a screwdriver to discharge a cap like that will burn/melt the blade like a battery would.

So If you don't have a High power Low Capacitance Cap elsewhere in the car, check at the array circuit boards (If they are accessible) look for an Electrolytic cap on the board, It will say something like : 150 MFD @ 25 WVDC, and have a + and - on it..See if the voltage is there.

Also, do you have a "Ballast" of sorts..on that system to cause enough Draw on the flasher to flash with a mix of incandescent and LED lamps? If so , It may be installed wrong or defective. Check for that.

Doc
Good Points Doc
Something else to try is with the ignition off flip on the turn signals to one side and see if the other side goes out. If there is a capacitor on teh board that the leds are attached to if you disconnect the plug to the board, theoriginal light plug, the bulb should stay lit with no connection. Also unplug both lights and test with your meter for voltage at the wiring, if it is a real low current leak you may see the voltage go back up to 12 volts when you remove the load. You may also want to take the front bulbs out to test. The problem could be up front also. It takes a lot more current to light an 1157 than an led. Thats for sure.
Also if you disconnect the battery and the light go out you know its not a capacitor in the line. This should be a real simple test. Just remove the negative battery cable.
This will eliminate a lot of possibilities
06-27-2007 03:39 PM
docvette Doc here,

An LED can possibly Run for weeks from the drain of an electrolytic Capacitor, provided the Cap was large enough..Like one of those OLD computer power supply caps, 1 MFD @ 100000 WVDC..(The ones that are so popular with Car Stereo Installers now..to keep high current drain stable on "Thump")

A Single LED would last for months on a fully charged cap of that type..a screwdriver to discharge a cap like that will burn/melt the blade like a battery would.

So If you don't have a High power Low Capacitance Cap elsewhere in the car, check at the array circuit boards (If they are accessible) look for an Electrolytic cap on the board, It will say something like : 150 MFD @ 25 WVDC, and have a + and - on it..See if the voltage is there.

Also, do you have a "Ballast" of sorts..on that system to cause enough Draw on the flasher to flash with a mix of incandescent and LED lamps? If so , It may be installed wrong or defective. Check for that.

Doc
06-27-2007 12:20 PM
cboy
Quote:
Originally Posted by T-bucket23
Have you checked with a volt meter to see if there is any power to the socket.
I've been trying to troubleshoot this all morning. I get a reading of 15-16 millivolts on the 200m scale of my meter. It is in the brake/turn/flashers wire not the tail light wire. (I'm using an arm type brake switch, not a pressure switch). I also checked it at the turn signals and I'm getting a similar reading on the red/black wire coming in from the brake light switch (attaches at the hazard flasher and the turn signal) Interestingly, when I disconnect the wiring harness for the steering column wires and test the red/black wire coming into the harness from the brake switch I do NOT get a voltage reading at the harness or at the turn signal. But when I couple up the harness again, I get the 15-16 mvolts.

I also tested all the other incoming leads in the wiring harness and did find one with about 15-16 mvolts. This is the white/red wire from the hazard flasher. BTW, I'm getting those readings at the harness and the turn signals with the fuse pulled out for the hazard/stop light circuit. However, the fuse is still in for the turn signal circuit. I'm headed back out to the shop now (mmmmm, nice lunch) and will pull that fuse and see what happens.

As you can guess, I'm pretty confused at this point (which is inevitably the case whenever I deal with the electrical system).
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