!@#%#ing lights

muskyfins

Chief Petty Officer
Joined
Jun 7, 2012
Messages
578
Been battling a light problem on the truck. Driving me freaking crazy. Can you guys help?:frusty:

Symptoms (tested with brand new magnetic lights)
Headlights off-brake lights good
Headlights on-brake lights good
Headlights on-no left turn signal/turn signal on truck only lights up and does not blink
headlights on-right turn signal ok
headlights and brakes on-no turn signals
headlights off-turn signals not tested recently (no data)

I'm also pretty sure there is an issue with the fog/daytime running lights.

Is it possible that if one or both of the DRL's are shorted, there is too much load on the system to flash the turn signals? Or is it redirecting so much voltage that there isn't enough to run the turn signals?
 
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redneck joe

Supreme Mariner
Joined
Mar 18, 2009
Messages
10,200
i'm no help just stopped by to tell you I feel your pain. My solution is always to rip out the old and install brand new.

And I just did.

And went LED.

And it worked.
 

muskyfins

Chief Petty Officer
Joined
Jun 7, 2012
Messages
578
this is on the truck side. I'm certainly not above trading it in.....but the admiral wouldn't be too happy
 

oldjeep

Admiral
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May 17, 2010
Messages
6,455
At least it is cheap to try it out. Make sure to get the HD version if available for your truck.
 

redneck joe

Supreme Mariner
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Mar 18, 2009
Messages
10,200
oh truck yeah missed that. Get new. I just did. This one's only 10 years old....
 

Silvertip

Supreme Mariner
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Sep 22, 2003
Messages
28,758
It would be nice to know the year, make and model of the truck in question as well as the make and model of the magnetic light bar you have.. There are a dozen or more possibilities but when weird things start to happen, there is generally a ground issue but there are many other things to consider.
1) Do the truck lights work fine with no magnetic lights connected. Yes or No. If yes, go to #2. If no, you have a truck issue that requires a totally separate set of troubleshooting.
2) Does the truck have amber colored turn signals, or separate turn signal circuits (a separate bulb from the tail/stop lamps). If so you need a converter for the lights. You are trying to operate a three circuit system from a modern four circuit system and they are not compatible.
3) Does the magnetic system have four wires just like a trailer wire harness?
4) Did you do the truck wiring or is this a factory trailer harness.

See -- There are more questions than answers because we can't see your stuff.
 

oldjeep

Admiral
Joined
May 17, 2010
Messages
6,455
It would be nice to know the year, make and model of the truck in question as well as the make and model of the magnetic light bar you have.. There are a dozen or more possibilities but when weird things start to happen, there is generally a ground issue but there are many other things to consider.
1) Do the truck lights work fine with no magnetic lights connected. Yes or No. If yes, go to #2. If no, you have a truck issue that requires a totally separate set of troubleshooting.
2) Does the truck have amber colored turn signals, or separate turn signal circuits (a separate bulb from the tail/stop lamps). If so you need a converter for the lights. You are trying to operate a three circuit system from a modern four circuit system and they are not compatible.
3) Does the magnetic system have four wires just like a trailer wire harness?
4) Did you do the truck wiring or is this a factory trailer harness.

See -- There are more questions than answers because we can't see your stuff.

It's still just a bad flasher ;)
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
I had a few problems with light a while back. Seems every little tinny light has its own fuse. I mean even the tag lights have a left bulb fuse and aright bulb fuse. So when something goes wrong, it is best to check all the light fuses and the actual light themselves. And whoever the brainiac was that designed the system, some light fuses are inside the vehicle and others under the hood. Imagine that... Not sure if you have a standard blinker plug in unit or the more modern circuit board blinker system. But not a bad place to start. JMHO!
 

muskyfins

Chief Petty Officer
Joined
Jun 7, 2012
Messages
578
It would be nice to know the year, make and model of the truck in question as well as the make and model of the magnetic light bar you have.. There are a dozen or more possibilities but when weird things start to happen, there is generally a ground issue but there are many other things to consider.
1) Do the truck lights work fine with no magnetic lights connected. Yes or No. If yes, go to #2. If no, you have a truck issue that requires a totally separate set of troubleshooting.
2) Does the truck have amber colored turn signals, or separate turn signal circuits (a separate bulb from the tail/stop lamps). If so you need a converter for the lights. You are trying to operate a three circuit system from a modern four circuit system and they are not compatible.
3) Does the magnetic system have four wires just like a trailer wire harness?
4) Did you do the truck wiring or is this a factory trailer harness.

See -- There are more questions than answers because we can't see your stuff.

Sorry silvertip. Anger getting the best of me.
2002 Chevy Avalanche 2500. Owned since 2003. Admiral's daily driver until 2013. Now mine. 177,000 miles. Factory trailer towing package including 7 pin wiring connector to hitch. Previously corrected ground wire issue at 7 pin connector harness. Loose wiring. No issues until recently.

1. No. Truck lights only/no additional lights hooked up-headlights off-no issues. Headlights on-left turn flashes fast and left fog light blinks exactly in sync with turn signal. Fog lights on, left turn signal lights and stays lit.
2. The truck has separate turn signals from tail/brake lights.
3. Magnetic system has 4 wires. Exactly like a trailer harness. This is not an issue with the magnetic set. (purchased brand new last night to bring home new trailer for the hunting boat) This has been ongoing (4 months +/-) with the truck and I've pushed my luck long enough with local law enforcement.
4. Factory harness.

Avalanches have common issues with water in the fog lights. Right fog bulb burns out within a day of installing new one. Left fog has flashing issue with headlights on. I am hoping there is a short in one of the fog bulbs sockets causing a voltage drop to the turn signal circuit. Easy to test, just need the weekend. Maybe have 10 minutes to try it tonight.
 
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bassman284

Commander
Joined
Jun 24, 2006
Messages
2,839
Just a guess, but could you disconnect the fog lights and then check things out? What I mean is, rather than trying to test out the fogs, just remove them from the equation.
 

pete j

Petty Officer 2nd Class
Joined
Nov 21, 2012
Messages
173
Got me scratching my head but bassman seems like the smart one on this subject :)
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
With a 7-pin connector on the truck and what I must assume (since you didn't tell us) is that you have a four wire flat connector on this light set. That means you have a 7-pin to four-flat converter cable that you must use to attach the light bar to the 7-pin (unless the 7-pin also has a flat four built into it.) If an adapter is indeed being used, are you certain it's wired correctly. Just for the record, anytime you have a rapidly flashing turn signal, that's an indication there is a bulb burned out somewhere in the system. When a bulb burns out, especially a dual filament as you have on this system, the burned out filament can fall onto the other filament and create a problem. I've also seen dual filament bulbs inserted incorrectly in the very cheaply made sockets. Dual filament bulbs have the locating pins offset from each other to prevent incorrect insertion. But, a determined gorilla-type assembler can force the bulb into socket which creates a problem. Rather than just jumping from one thing to the other, break out your battery charger and a small nail. Plug in the charger and put the nail in the positive clip. Connect the negative clip to the pin with the white wire on your magnetic light. Now touch the nail to each of the other three pins to ensure the right and left turn signals light (these are the brighter than the running light). The brown wire is the running light, touching that pin should light both of the running lights. Now you know the light system is good. Or you could connect the lights to another vehicle. Either way you prove the lights are good and the problem is with the truck or the adapter if you are using one.
 

NYBo

Admiral
Joined
Oct 23, 2008
Messages
7,107
1. No. Truck lights only/no additional lights hooked up-headlights off-no issues. Headlights on-left turn flashes fast and left fog light blinks exactly in sync with turn signal. Fog lights on, left turn signal lights and stays lit.
Dollars to donuts, you have a bad ground in the left front lighting harness.
 

muskyfins

Chief Petty Officer
Joined
Jun 7, 2012
Messages
578
Ok, little update. In the end, as long as I have turn signals, brake lights and trailer lights, I don't care about the fog lights. So I removed all fog light bulbs and used the known working magnetic light set and confirmed the following:

Headlights off/No trailer lights:
Left turn signal fast flash.

Headlights on/no trailer lights
everything works correctly.

Headlights off/with trailer lights
everything works correctly

Headlights on/with trailer lights
everything works correctly

It may have something to do with the flasher, but as long as everything is working, I'm going to move on to bigger boat issues. Thanks for all the replies.
 
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gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
muskyfins, did you replace any of the bulbs in any of the lights? And did you replace the actual flasher itself. The reason I ask is because I had a fast flasher and even though the bulbs were lighting, one was causing that to flash fast. So after I replace the bulbs, it worked correctly again and I haven't had a problem since. So even if the bulbs look good or even light, you may consider replacing them (one at a time) to see which one is causing your problem... Just an idea, and bulbs really aren't expensive or hard to change either. JMHO!
 

muskyfins

Chief Petty Officer
Joined
Jun 7, 2012
Messages
578
I did not replace any bulbs. Only removed all fog light bulbs. For now, I'm legal and safe. After the boat is in the water, I might revisit this issue. I'll check grounds, bulbs, flashers, and look for shorts. But I've gotta get my girl ready for the water. That is priority #1.
 
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