Posts Tagged ‘rapid flash’

I’m sure you already know that LEDs are polarity sensitive. If you didn’t know this basically means that they will not light up if the power and ground are connected backwards. So if you plug in you new V-LEDS and they do not light up, try flipping them around and plugging them back in and they should work. I want to go over some other polarity issues where flipping the connection over will not work.

Here is the classic example. Your car, truck, or motorcycle uses an 1156 style bulb and you have replaced your blinker or brake light and it won’t light up. The filament bulb that was installed before worked just fine, why is the LED not working? Simple answer is polarity. The problem here is that you can’t just flip this bulb around to make it work. The metal base is the main contact and there is a center pin in the bottom of the socket that is the other contact. The problem here is associated with the wiring on your car. The wires going to the socket are backwards. The industry standard is the metal base is the ground connection and the center pin is the power connection. Some car makers do it differently and use the metal base as the power connection and center pin as the ground connection. Why? Not too sure but it is easily fixable if you have some tools. You will simply need to cut the 2 wires routed to the plug and reconnect them backwards. Solder and heat-shrink the connections if you have the a soldering iron, otherwise a simple, crimpable, butt connector will do the trick. I have found on some cars this is not possible, usually European cars with one piece buss bar socket setups like the picture shown. You cannot modify the wiring for these sockets as all the bulbs share a common ground wire or common power supply. If you find that your car has this type of tail light assembly I highly recommend testing it with a test light to see if it is wired backwards before you purchase any LEDs.

Another polarity issue that can be a problem is on some blinker circuits. Known vehicles are the newer Jeep Grand Cherokee and Wrangler and some GM trucks and SUVs. These vehicles have a 194 sidemarker bulb that also acts like a blinker. When the parking lights are in the OFF position this bulb is off. Once you turn on your turn signals this bulb flashes on alternately of the front blinker. When the parking lights are in the ON position this bulb is on. Once you turn on your turn signals this bulb flashes off alternately of the front blinker. This is a series circuit that is fed power from 2 sides. It requires that voltage and ground be able to flow both directions through the filament of the 194 bulb. Once you replace this bulb with an LED the power cannot flow through and will cause the blinker to stop working. We have some 194 LEDs with special circuitry that will work for this application, but they are Flank style LEDs and usually do not work for this light housing application (light is shining the wrong direction).

So if you find that you are experiencing one of these problems grab a test light and test your sockets. Or put the filament bulb back in and see if everything is working.

Thanks for reading. Feel free to leave a comment or ask questions. You can leave them here or email them to me directly here: tech@v-leds.com

James the tech@v-leds.com

Hello everyone, I get emails from you on a daily basis asking why your Hyper-Flash problems came back after installing resistors to fix it. There are a few vehicle and product related issues that can cause this. Lets go over these and see if any of them apply to you, or if this happens to you in the future you know what it could be.

Lets cover the basics here. What is “Hyper-Flash”? There is a part in every car that controls the pace of you blinkers. It is called a “flasher”.  It also has a 2nd function, letting you know your blinker is burnt out. It does this by doubling the pace that it blinks your lights. It is quite annoying, and it should be. You don’t want to be driving around without working blinkers, it could cause an accident! Unfortunately the same thing happens when you replace filament bulbs with LEDs. Why? The “flasher” measures the “load” or “wattage” the filament bulbs are drawing through the circuit. When you replace them with LEDs this draw drops down to almost nothing. (remember that LEDs are very efficient and do not draw much power) So now your flasher thinks the blinkers are burnt out and starts “Hyper-Flashing” You have 2 options to fix it, replacing your flasher with an LED specific version or installing Load Resistors on the blinker circuit. (How to know which one of these products to use will be covered in a future post, right now I want to get to the topic at hand) So you have fixed this in your car and everything is working great! Then all of a sudden, for NO reason whatsoever at some random time your blinkers start “Hyper-Flashing” WHY?

I will always assume it’s the installation of Load Resistors. Not because I don’t think you know how or what your doing when it comes to installing parts on your car, but because that would be the first thing I would check if something I worked on came back to me with a problem. I will always do my best install on every job, but  I am human and will eventually make a mistake, so will you. So check your splice taps for a solid connection. Inspect for a loose ground wire, or for corrosion on the connections. If all that checks out and you still have an intermittent problem you may need to ask yourself this one simple question: “What other products did I install on my car just before this started happening?”

8 times out of 10 the answer to that question is “I installed aftermarket HIDs”!  After noting this trend I started skipping the “check your connections” question and started asking “Did you install HIDs in your car?” Another interesting thing about this is the fact that 85% of people who experience this specific problem owns a GM car or truck! A Chevrolet, GMC, Saturn, Buick, Pontiac, etc. You get the idea right? Then I started to ask myself “Why do so many General Motors products have this common problem?” After working on a friends GMC 2500 HD pickup I figured it out! *GROUND WIRING* I recreated this problem on his truck and found another issue in the process. (i will get to that in a bit) I found that his headlight, high-beam, parking light, blinker, and DRL bulbs all share a single ground wire!  (a notably small ground wire too) Everything works great until you turn on the low beams (which we converted to HIDs) So after trying different things I came to the realization that all the bulbs were on a single ground, the HID ballasts were plugged directly into the trucks headlight socket, and the ballasts were causing resistance in the ground for the blinkers and the Load Resistor I installed on the blinker circuit. So I re-grounded the HID ballast to a bolt on the radiator support and BAM! It fixed it! Hopefully this shines some light on a problem you are experiencing right now and you can fix it, or for someone you know who may have that problem.

I want to cover the other issue I discovered on this truck, it is specific to our White/Amber “Switchbacks“. The problem I found with the switchbacks is not a problem isolated to GM vehicles or having installed HIDs on your car. It is related to the subject matter at hand “Resistance to Ground” and “Load” on the Blinker circuit, and with this particular product, back feeding or stray voltage. First I will explain the problem, which I receive multiple tech emails about too. After installing the switchbacks they worked great until I turned on the headlights. As soon as the HIDs came on the White LEDs started to fade out, and then struggled to stay on. I turned on the blinkers and the Amber LEDs worked just fine. Then the White LEDs stayed off completely until I turned off the HIDs.  Weird huh?! So after I moved the ground on the HID ballast they worked great for a few minutes with the head lights on. I turned on the blinkers and noticed that on one side the white LEDs were struggling again. What was going on now? I grabbed my test meter and checked the voltage on the parking lights, full power was there. Then I tested the blinker and it was fluctuating at about 1.5-3 volts! Why? That did not seem correct to me. So  I disconnected the 6 OHM 50 WATT Load resistor and reinstalled the stock filament bulb. I then retested the circuit and there was not voltage on the blinker circuit. Long story short: The filament of the bulb is “bleeding” off that voltage in the blinker circuit. Why didn’t the resistor that was installed do the same thing? I installed a 3 OHM 50 WATT Load Resistor this time and, BAM! It fixed it. The circuit needed a larger load to fully bleed off the stray voltage. This problem also pointed to our lineup of Switchback LEDs. It is only on our type 2 version, which turns off the white LEDs when the blinker is being used. The power controller that turns off the white LEDs is sensitive to that voltage, but it is not enough to turn on the Amber LEDs. Not all cars will have this issue, but if you are experiencing some of these this is a good place to start.

So in conclusion, Don’t ground your HIDs to your cars head light socket. Or better yet install a relay harness at the same time and avoid this problem from the get go! (see my post on Why should I use a relay harness with my HID kit?) And if your switchbacks are acting like I described now you know what you can do to get them working correctly, Install a 3 OHM 50 WATT Load Resistor to bleed off any stray voltage.

Thanks for taking the time to read through all of that technical blah blah blah. I hope that this did not get too confusing, but if you need a clearer answer or want to discuss a similar problem that I did not cover feel free to leave a comment or send me an email directly at tech@v-leds.com.

James, the tech at V-LEDS.com