United Pacific LED Tails

[_1966ChevyPU]

Hey guys, been awhile since I've been on... a LOT has changed with my truck.

My latest endeavour has been to put United Pacific LED tails (CTL6066FSLED) and parking lights (CPL6066A) on the truck. I started with the parking lights and that swap went perfect. However when I want to do my tails, I found that they did not work correctly. I sent an email to Unitied Pacific and was told I needed to get a flasher (90652) for them to work.

Ok... I did that but they still don't work. They come on when you turn the lights on (dim) and they light up when you hit the brakes (bright). But when you hit the turn signals, they don't do anything. I put the OEM tail back in and it and the LED parking lights work as should. Put the LED tails back and they don't flash. I called United Pacific and after talking to them and trying their tricks (with and without polarity switch, metering and jumping) he suggested that I have a bad switch. While possible... I'm not sure and don't want to just swap it out without hearing from others who may have run into this.

Any help is appreicated

[fleetsidelarry]

Are you sure that is the correct flasher for LED lights? (edit: I see that it is supposed to be for LEDs) it still sounds like you need more impedance in the curcuit

my truck has LED taillights but regular bulbs up front and works fine with the OEM flasher.

my '48 has LEDs front and back and required a special flasher.

there are also in-line resistors that you can purchase for each circuit.

I don't see why it would be the switch if it worked both before (with all regular bulbs) and when you had LEDs in front and regular bulbs in back.

try bypassing the switch temporarily with a jumper

[_1966ChevyPU]

That's what I was told from United Pacific when I called them the first time.

And it's an American Autowire kit I used to rewire the truck.

[fleetsidelarry]

sorry, I edited my post while you were replying. the switch they were referring to is the light switch? or the turn signal switch?

although I was referring to by-passing the light switch, now that I think about it (3rd cup of coffee), I don't see how the light switch even matters.

[tincan1966]

I've only had luck using the flashers that have the added ground wire on them for LEDs.

I am sure you have checked, but are the tail lights grounded REALLY well?

Since there are only the two wires to the LED lights, I would assume the light is ok, since both circuits work(tail lights and brake lights-and brake and turn are the same wire)

I would try a good grounded flasher, and make sure you have great grounds for the bed, even add a 10ga wire bolted to the frame and to the bed.
These trucks are extremely touchy about grounds and it's only amplified when adding LEDs.

I've used United Pacific for several years, and for what it's worth, never had a complaint on product.....

[fleetsidelarry]

Originally Posted by tincan1966

these trucks are extremely touchy about grounds
.....

x2

[_1966ChevyPU]

Originally Posted by fleetsidelarry

sorry, I edited my post while you were replying. the switch they were referring to is the light switch? or the turn signal switch?

although I was referring to by-passing the light switch, now that I think about it (3rd cup of coffee), I don't see how the light switch even matters.

Yes, I'm referring to the turn signal switch, not the actual pull-the-knob switch.

One of the things he had me do was make a jumper that would bypass the relay and it still did not work, which is why he said he thought it was the switch because it wasn't making a good enough contact and getting enough voltage through the system.

Originally Posted by tincan1966

I've only had luck using the flashers that have the added ground wire on them for LEDs.

I am sure you have checked, but are the tail lights grounded REALLY well?

Since there are only the two wires to the LED lights, I would assume the light is ok, since both circuits work(tail lights and brake lights-and brake and turn are the same wire)

I would try a good grounded flasher, and make sure you have great grounds for the bed, even add a 10ga wire bolted to the frame and to the bed.
These trucks are extremely touchy about grounds and it's only amplified when adding LEDs.

I've used United Pacific for several years, and for what it's worth, never had a complaint on product.....

By "flashers that have the added ground wire on them for LEDs" do you mean the flasher relay with the added ground?

The LED tails have the same plugin as the bulb... but no, I have not had the chance to get back under the truck to check all the wiring again for grounds.

[tincan1966]

Yes the flasher or relay as some call it, has a ground wire coming directly off of it that needs connected to a good body ground. These are also called "no-load flashers" since the LED do not have the amperage draw of normal bulbs, which is what makes a regular flasher relay work.

Since you have only the 2 wire connector on the tail lights, I would definitely add a wire from the frame to the bed, assuming you already have one up front from the battery or engine to the frame. You can also just add a 10ga wire from the cab sheet metal to the bed underneath and accomplish the same thing. These beds to do not ground sufficiently thru the bed bolts for the LED bulbs.

[fleetsidelarry]

Originally Posted by _1966ChevyPU

(1.) One of the things he had me do was make a jumper that would bypass the relay and it still did not work, which is why he said he thought it was the switch because it wasn't making a good enough contact and getting enough voltage through the system.


(2.) The LED tails have the same plugin as the bulb... but no, I have not had the chance to get back under the truck to check all the wiring again for grounds.

Bryan

1. the thing I don't understand about the logic of the turn signal switch not being good is that the flasher actually works fine if there's more impedance, correct? which implies to me that the turn signal switch is supplying current just fine. I believe the original flasher wasn't what I think of as a relay, but rather a momentary thermo switch with just a power in/out. unless the new wiring changed the flasher to a relay.

2. as was mentioned by tincan, there is no ground wiring on these lights, they ground (when they do) via the screws that attach the buckets to the sheet metal.

when I reassembled my bed and reinstalled my LEDs I had one side that just did not want to ground the bucket

[_1966ChevyPU]

Originally Posted by tincan1966

Yes the flasher or relay as some call it, has a ground wire coming directly off of it that needs connected to a good body ground. These are also called "no-load flashers" since the LED do not have the amperage draw of normal bulbs, which is what makes a regular flasher relay work.

Since you have only the 2 wire connector on the tail lights, I would definitely add a wire from the frame to the bed, assuming you already have one up front from the battery or engine to the frame. You can also just add a 10ga wire from the cab sheet metal to the bed underneath and accomplish the same thing. These beds to do not ground sufficiently thru the bed bolts for the LED bulbs.

Although I have not mounted the ground wire on the flasher "for good", I have mocked it onto a ground and have verified with a multimeter that it is a good ground. I will crawl under the truck next chance I get though and verify no ground to the bed (don't recall putting one in when running the kit) and see if that fixes it.

Originally Posted by fleetsidelarry

Bryan

1. the thing I don't understand about the logic of the turn signal switch not being good is that the flasher actually works fine if there's more impedance, correct? which implies to me that the turn signal switch is supplying current just fine. I believe the original flasher wasn't what I think of as a relay, but rather a momentary thermo switch with just a power in/out. unless the new wiring changed the flasher to a relay.

2. as was mentioned by tincan, there is no ground wiring on these lights, they ground (when they do) via the screws that attach the buckets to the sheet metal.

when I reassembled my bed and reinstalled my LEDs I had one side that just did not want to ground the bucket

I didn't really understand either how the switch is bad if it's working either... that's what the guy at United Pacific told me while on the phone to try and get it working. lol

I'll put a wire from the frame to the bed (although without being under there and just trying to picture in my head... where's a good place to do that so a screw won't show?). So if the lights are grounded through the screws, does that mean that the two wires going to the lights are not power and ground?

[fleetsidelarry]

Originally Posted by _1966ChevyPU

does that mean that the two wires going to the lights are not power and ground?

one of the wires is tail light power (from the light switch), the other wire is brake/turn (different wire for left and right), usually these are brown for tail and green and yellow (right and left brake/turn). the wires to the park lights are different colors.

http://67-72chevytrucks.com/vboard/s...d.php?t=324713

[66_c10_tpi]

Just an idea. Try putting back in the original bulbs in the front turn signals and hooking up the rear with the leds. This should tell you if you have a problem in the rear or just not enough load with both front and rear leds.