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Old 08-31-2021, 10:23 AM   #1
Rickysnickers
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Fast blinking turn signals

Here's the info. I have LED headlights, LED front turn signals, and rear LED taillights/turn signals. I installed two of the LED style flashers, that have a ground wire coming off of them. One is for the turn signals and the other is for the hazard lights. The ground wires are attached to clean metal.

Last week, I got under the truck and ground down some nice clean metal and installed several ground straps. I have;
1. Cylinder head to frame
2. Cylinder head to transmission
3. Transmission to frame
4. Battery to frame
5. Body to frame x2

I tested the blinkers with the engine off and the flash rate is normal. However, when the engine is running, they are flashing quickly and at an irregular rate. What is going on?????
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Old 08-31-2021, 11:37 AM   #2
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Re: Fast blinking turn signals

Good job on the ground straps btw! Which brand of LED light and flasher did you use? I have heard the term "hyperflashing" to describe your issue, here is some info on it that might be helpful:

https://www.superbrightleds.com/blog...rflashing/275/
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Old 08-31-2021, 04:57 PM   #3
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Re: Fast blinking turn signals

LED flasher rate is electronic so load has nothing to do with it. You stated they work normally when vehicle is off. Maybe start checking voltage at flasher and bulbs with vehicle on and off.
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Old 09-02-2021, 09:55 AM   #4
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Re: Fast blinking turn signals

Thank you both. Unfortunately, I need a round LED flasher. I looked on that website and only found the square type. The ones I have were purchased off of Amazon. I'm wondering if they are any good.

Not to sound dumb, but I am bad at electrics. How do I check the voltages?
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Old 11-16-2021, 01:51 PM   #5
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Re: Fast blinking turn signals

Are your front turn signals built in to the headlights? Those may be designed to have a hyper flasher.

Are your rear lights just bulbs in the stock socket or led inserts?



I don't have led front turn signals, only these led taillights
https://www.classicparts.com/1941-53...info/49-212LR/


I used these flashers
https://www.amazon.com/Keep-Clean-10...18980439&psc=1
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Old 11-16-2021, 04:00 PM   #6
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Re: Fast blinking turn signals

No, the front turn signals are in the stock location, separate from the headlights. The rears are inserts. The issue started when I added the front turn signals. I have an LED flasher and LED hazard relay. I even bought a third one and replaced the turn signal relay with that one and I still have the same results.
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Old 11-16-2021, 04:17 PM   #7
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Re: Fast blinking turn signals

Did the front signals work with standard bulbs?

It could be you got the wrong bulbs, there are some a similar size with the contact point in the wrong place. If you can, compare the contact points on the original bulbs to the new LED bulbs.

If you do have the correct bulbs, you could try the no load flashers I mentioned above or something like this resistor kit
https://www.superbrightleds.com/more...rning-fix/190/
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Old 11-16-2021, 04:30 PM   #8
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Re: Fast blinking turn signals

Yes, everything worked as it was supposed to, prior to changing the front turn signals. Once those were installed, that's when the issues started. I don't have the stock turn signals anymore, and if I do, I have no idea where they are.

So, my question is, why would everything work as it should, with all the LEDs in place, with the key on and engine off? When the engine is running and the blinker is turned on, the irregular flashing and high flash rate starts.
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Old 11-16-2021, 07:33 PM   #9
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Re: Fast blinking turn signals

I would try the resistors. You battery is probably 12volts and when you start your truck that could increase to 13 volts or more.

The increase could be enough to effect the leds.
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Old 11-16-2021, 07:43 PM   #10
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Re: Fast blinking turn signals

Possible something is putting static into the electrical system with the motor running. The old style bi-metal flasher didn't care about static but the new electronic ones are probably more sensitive.

Check that you don't have a plug wire close to another wire.
Make sure all the battery and alternator connections are tight and cables good.
As others mentioned, check your voltage. Possible the voltage regulator is bad and your alt is putting out too much voltage.
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Old 11-16-2021, 08:17 PM   #11
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Re: Fast blinking turn signals

I'm an electrical dunce, admittedly. How do I check the voltages in the turn signals (I'm assuming that's what you are referring to)? I have a volt gauge in the instrument panel. It says I have right around 13.5 to 14 volts when running.
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Old 11-16-2021, 08:32 PM   #12
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Re: Fast blinking turn signals

when I fab and install a battery ground cable I always go to the frame and the engine block. the biggest draw in the system will be the starter which is bolted to the engine block or the transmission so that is the first run from the battery. from that bolt on the engine I also attach a cable that goes to the frame. the frame is a front to rear conduit for other grounds for lights etc. from there I install a ground from the frame to the sheet metal stuff like the cab, box, rad support etc as needed. when I am wiring a unit from scratch I do this as well but always try to run a dedicated ground wire for the accy that are outside the cab.

a regular old fashioned test light with a filament style bulb is simply a bulb with a wire and ground clamp connected to one side of the bulb and a sharp probe connected to the other side. since the filament inside the bulb could care less which side is positive and which is negative you can connect them whichever way you need to for your test purposes. these draw more than an led test light will. led test lights are polarity sensitive so you need to connect the ground to the negative side of things if doing a test using the tester inline with the circuit but not connected to a dedicated frame ground, say. old styles testers can sometimes draw more than the circuit in a newer style vehicle is made to handle so the led testers, or a multimeter, are recommended.

how to use a multimeter. if buying one try to get one that will also have provisions for an alligator style clamp so you can clamp it onto a wire or a ground point

https://www.youtube.com/watch?v=c9KNAIjoEYs

on your truck
I would start by checking
-the light assembly to ensure the bulb has a good contact with the bulb holder and the contacts under the bulb are shiny and the spring that keeps pressure on the bulb is still working and not hung up. when you insert the bulb there should be some resistance felt and once in place the bulb should be held against the socket by 2 little pins in the socket slots. this ensure a good connection between the bulb and the socket which is the ground for the bulb.
-compare the new led bulb with an old bulb from the style of bulb holder you have. if it has marker lights and signal lights then it will have 2 contacts and will likely be an 1157. if ity is a single circuit then the bulb may have been an 1156. these bulbs have a couple of little pins that help align the bulb in the holder so the bulb contacts sit in the correct spot to line up with the appropriate contact in the bulb holder. on the double element/circuit bulb (1157) one of these pins sits deeper down on the barrel of the bulb than the other one does. I have had new bulbs from a reputable supplier where the pins were reversed so marker was signals and vice versa or they were totally not in the right spot so both contacts on the bottom of the bulb hit both contacts on the pigtail.
-check for voltage at the light, down inside the light socket but be sure to wrap the tester bare metal parts first with tape, with the bulb removed (or remove the bulb and pull the pigtail wires up through the bulb holder so you can get a better connection without possibly grounding your tester on the bulb holder). ensure you connect your ground first to the frame to get actual voltage available, then do the same test with the ground attached to the bulb socket and see if there is a voltage drop in the circuit which could indicate a poor ground. see what you have for voltage with the engine off-lights on, then signals on, then start the engine and see what you have for the same tests. also check battery voltage not running and then running and compare these results. it's good to write your finding down when you do these tests.
-check the light for a good ground. since both lights are doing it and only since you swapped out to the led bulbs it seems like the problem could be something didn't like being disturbed and a poor connection was the result. I would say that possibly you have a grounding problem on the front sheet metal somewhere or from the bulb holder to the ground. possibly the flasher you have is made to do rapid flashing and does so when the engine is running because the voltage is higher and can overcome some voltage drop from a poor ground. what you may try is a simple jumper wire or booster cable from the battery or the frame over to the front sheet metal where the lights are getting their ground from, like right on the screw head if possible. if the lights have a ground that relies on sheet metal for a connection, like a rad support is common on a lot of these trucks, then that sheet metal needs to be connected to the frame somehow. just grounding the cab and not the front fender or rad support where the light is grounded means the ground needs to go from the battery to the frame or engine then to the cab then through the cab to a fender or inner fender mounting bolt then through that to a rad support bolt so the light can get a ground finally. there are lots of places for the circuit to develop resistance through all those connections. personally, when I wire a light, I try to get a dedicated ground for the light's ground wire. if it's a front signal light like this I will extend the ground wire on the light so it reaches the truck frame rather than ground it on the sheet metal. if the bulb socket relies on the sheet metal body of the light for a ground then I will attach a ground wire to the light housing or the bulb socket housing if possible and then run a ground to the frame. firstly because I want a good ground and secondly because I hate making a screw hole in the sheet metal that will inevitably become a rusty screw hole and a poor connection. on the frame I will buff it down to bare metal, attach the ground wire(s) with a star washer under the wire or under the head of the bolt. I use plated fasteners and try to use a bolt and nut rather than a screw and then when I am done the project, it is tested and found operational, I coat the connection with high zinc paint like weld through primer or I use aviation form a gasket to coat all the surfaces.
-if all seems to be good you could try removing the flasher unit and installing a jumper wire where the power and load terminals are in the flasher bracket. this will eliminate the flasher so when the signals are turned on the signal bulbs will simply come on and not flash. you can try this with the engine running or not.
key off, the signals should not flash, just the 4 ways, head and tail lights and the brake lights should operate.
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Old 11-16-2021, 08:59 PM   #13
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Re: Fast blinking turn signals

There are sooo many turn signal flashers out there... "I need a round flasher" doesn't give enough information. Do you have a two or three wire flasher? What is the flasher part number? Sometimes it's important to be able to look at specs.

Quote:
So, my question is, why would everything work as it should, with all the LEDs in place, with the key on and engine off? When the engine is running and the blinker is turned on, the irregular flashing and high flash rate starts.
Very hard to say without testing. If you want to assume the flasher and LED's will work fine together, we can run through guesses.

It's possible that the alternator is producing some A/C. If you remove the alternator electrically and the problem disappears then you have a clue the issue may be caused by the alternator.

It's possible your ignition system is causing a problem. Spark voltage leaking from wires or engine compartment wires running parallel to a coil or spark plug wire could cause voltage spikes. You could try moving wires in the harness or spraying water on the plug wires and watching for a corona of blue sparks.

It's possible the turn signal flasher doesn't correctly recognize the voltage changes between "light on" and "light off." Or it's possible that it is still a current sensing flasher rather than a true voltage sensing device and the change in current flow is so minimal that the circuitry doesn't operate correctly. Changing to a true voltage sensing flasher could help with this.

It's possible that a fan or other device in the truck is not grounded properly and is trying to ground through a light circuit. Figuring out which device may be on when the truck is truck is running would be a key part of diagnosing this issue.

It's possible that your charging voltage is too high and the electronic circuitry in the flasher is trying to regulate voltage to the lights. Highly unlikely, but possible. Getting flasher specs could help with this.

It could be, as mentioned earlier, the rear LED bulbs are wired incorrectly for the vehicle and are causing a short between circuits. It could also be the pins are not aligned with the contacts or the pins are at same height allowing the bulb to be installed incorrectly. I've had to diagnose all of those issues. Changing to different LED bulbs could help with this. Using a meter to check the LED orientation could also help with this.

It seems like there are too many problems with aftermarket LED installations. We use LED lights in many vehicles in our fleet. They are quality lights and the price generally reflects that. We generally don't see the problems that are reported here on the forums.

If you want to try diagnosing the problem, I'm sure there are folks here that can help. Get yourself a test light (a bulb style, not an LED style), a digital volt and ohm meter, and some type of old fashioned tail light that can be used to substitute for an LED light. With those tools handy I know you'll get help.

Last edited by 1project2many; 11-16-2021 at 09:05 PM.
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Old 11-17-2021, 12:55 AM   #14
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Re: Fast blinking turn signals

post up some pics of the light inside where the bulb socket goes, and also the led bulbs. the flasher wouldn't hurt as well. just so we can see what you have. ensure the socket where the flasher plugs in is getting power to the same terminal as the flasher requires.
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Old 11-17-2021, 01:25 AM   #15
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Re: Fast blinking turn signals

it is common to have around 14.6 volts when running.
like mentioned a few posts back, electrical interference from the alt may be causing static that the flasher is sensitive to. you may need a different flasher that isn't so sensitive. you may also have just received a dud flasher.
some interesting reading

https://www.youtube.com/watch?v=9PyC_tFHKJE

https://www.motortrend.com/news/ligh...-flasher-leds/
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Old 11-17-2021, 11:08 AM   #16
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Re: Fast blinking turn signals

Wholly smokes! That's a lot of info. It will take me a bit to read and re-read it all. I will get some pictures for you Dennis. 1project, I will try to get the part number or link to the flasher relay I have so that you can take a look at it. BTW, here's the front turn signals I have. Installing these is what started the issues I have been having. https://www.speedwaymotors.com/Unite...ns,406244.html

Last edited by Rickysnickers; 11-17-2021 at 11:26 AM.
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Old 11-18-2021, 01:17 PM   #17
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Re: Fast blinking turn signals

I kind of went down a rabbit hole from your other post about this and the link in this post. I looked on-line about flickering LEDs and found too much information. The fact that your turn signals work with the engine off, and then flash faster with the engine on would lead me to think the engine is effecting the flasher module. I know you can get a noise suppressor to keep engine noise out of the radio, why not put one on the supply to the flasher module. It's usually either a coil in-line, or a capacitor to ground. I found some with both. Here is a link to a site with a nice picture, you could probably get one at your FLAPS: https://radiogagas.com/product/25a-a...utm_term=33517
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Old 11-18-2021, 02:34 PM   #18
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Re: Fast blinking turn signals

I need a round LED flasher. I looked on that website and only found the square type.
Use spade terminals and a short ("1") wire. You could use the set up to adapt and style flasher, round or square) to the circuit.
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Old 11-20-2021, 10:18 AM   #19
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Re: Fast blinking turn signals

You looking for this?
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Old 11-20-2021, 11:31 AM   #20
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Re: Fast blinking turn signals

Quote:
Originally Posted by crossfire84 View Post
You looking for this?
That's the one I currently have. I will have some time to day to fool around with this. Thanks everyone for all the pointers and help.
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Old 11-25-2021, 10:19 AM   #21
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Re: Fast blinking turn signals

Update for you all. I had some time yesterday so I looked around to see what I could see. The issue ended up being a grounding problem and relay. The ground wire coming from each of the front turn signals, was not contacting bare metal. That problem taken care of. Now I have two different relays for the hazard and turn signals. I started the truck and the turn signals were still doing the fast, irregular blinking. However, I turned on the hazard lights and they worked fine. I swapped out the two relays and traded places. The turn signals worked as they should and the hazards had the issue. I ordered a new relay yesterday. I am now happy with these things, finally. Here's a link to a properly functioning LED relay.

https://www.amazon.com/CEC-Industrie...29658386&psc=1
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