Posts Tagged ‘Electronic Flasher’

Before we get started  I need to preface this article with a disclaimer. This is not a modification that should be attempted by everyone. This is only a guideline for those who fully understand how what they are trying to accomplish. V-LEDS cannot be held responsible for any damage that occurs to your vehicle while performing this modification. With that out of way lets get started.

This modification is relatively simple. I have done this before in the past, but never really thought much about it because we offer electronic flashers and load resistors that fix hyper-flashing issues. But what about the cars that we don’t have an electronic flasher for? Or for that customer who does not want to splice load resistors into his wiring harness. You can also look at this from an efficiency viewpoint. LEDs are very energy efficient and load resistors burn power to create an electrical load to trick the flasher unit, this defeats using the LEDs for this purpose.

Lets cover why you would even do this in the first place. We do not offer electronic flasher units for every car or truck out there.  If you happen to own a newer Honda/Acura you know that already. It is pretty spendy for the GM vehicles that use the LM487 flasher and Lexus vehicles lose the confirmation light flash of the security system when you replace the flasher unit with and LED compatible version. What if you could just modify the flasher unit that came in your car? How would you go about doing it? Before you modify anything you should probably understand how it works. Lets start with understanding how the flasher unit knows when your bulbs burn out.

As with any electronics, flasher units function within a set of rules. These rules are pretty simple when it comes to a  flasher units hyper-flashing circuitry. The rule here is wattage and the flasher unit is looking for a specific value of wattage. The flasher unit monitors the wattage of both blinker circuits (any car that uses these style of flasher units will  have 2 blinker circuits, a left and right) and compares the value of these circuits to a resistor that is located on the circuit board of the flasher unit. The resistor is a metal “HOOP”. This hoop is designed to be within a specific wattage range, anywhere from 42-54 watts depending on the wattage of your cars original blinker bulbs.  See the diagrams below to see what the hoop looks like. Depending on your vehicle, it  may look different from these examples.

Toyota/Lexus Flasher Unit

Typical Ford Flasher

So now that you understand how this part of the blinker circuit functions we can start to understand what needs to be modified in order for it to work with V-LEDS. We already know that LEDs have an much lower wattage draw than the filament bulbs. Another factor to consider is that an LED actually stops voltage. LED is the acronym for Light Emitting Diode, and diodes do not carry any electrical resistance (OHMS) across the positive and negative contacts. This changes the value of the blinker circuit and the flasher unit recognizes this as a burnt out bulbs and starts to hyper-flash.

This simple modification will allow you to change the value of the flasher units resistor hoop to match the value of your V-LEDS. After you have removed your flasher unit from your car and removed its cover take a look to see if yours has the resistor hoop. If you find that yours has the hoop you can go ahead and start, the process is pretty easy. All that needs to be done is to remove some material thickness from the hoop. This will change the value of the hoop, and by doing so changes the value to match that of your V-LEDS. You can use  a dremel tool with a sanding drum or something similar to do this, either way you do it be sure to take your time. Be sure you do not overheat the hoop, you can melt the solder joint on the circuit board. Grind small amounts of material off of the hoop. I ground down the face of it first and then ground down the top of it. Reinstall the flasher unit and test the blinkers periodically to ensure that you get it just right. While tested I found at one point the blinkers were flashing normally for about 5 seconds then would go back to hyper-flashing for a few seconds and  would continue to go back and forth. I ground off just a little more and it worked flawlessly. If you get this just right the flasher unit will function the same as it does with the filament bulbs. This means that if one of your V-LEDs stops working for some reason the blinker circuit will hyper-flash to let you know. That is what I consider a bonus!

The process is really quick and painless.  After I removed the flasher unit it only took about 15-20 minutes to grind it down while testing it. After about the 5th time I got it perfect. It is a pretty straight forward job once you understand what needs to be done. The picture on the right shows how the hoop should look when it is complete. All that’s left to do is to place the cover back on the flasher unit and install it in the car.

Go ahead and test it out for yourself and see how it works. Let me know if it works for you too.

Thanks for reading. Feel free to leave a comment or ask a question, or you can contact me directly via email: tech@v-leds.com

James, the tech@v-leds.com

Hello again, I have been receiving a higher volume of emails concerning replacing your blinkers with LEDs. Most of them pertaining to the faster flash rate (Hyper-Flash) that occurs when doing so, and if there is a way to get them to flash at the normal pace again.

This is a very common question. The answer is YES, it can be fixed. Here at V-LEDS we only know the fixes for the cars we have directly worked on ourselves. We log the information so we can help when needed. We still get questions from customers who are either confused by what they may have read on a forum or who are still unsure of what is needed. I hope that I can answer some questions surrounding this issue.

Lets cover why they start Hyper-Flashing in the first place. The answer is safety. Vehicle manufacturers use this feature to let you know when one or more of your blinker bulbs has burned out.

How does the car know? There is a part in the car that controls this. It is called a flasher unit. Each cars flasher unit is designed to monitor the electrical load that it is powering. This basically means that the flasher unit knows how many watts your cars bulbs will draw when they’re on. It monitors the cars circuit as Left and Right, or monitors all 4 bulbs independently. When one of the bulbs is burnt out, removed, or replaced with a lower wattage bulb or LED the flasher does its job and starts Hyper-Flashing on the side of the car that this has occurred.

Correcting Hyper-Flash when you upgrade to V-LEDS is relatively easy once you understand what needs to be done. Lets cover the easiest route first. If you are lucky to own a car that has a replaceable flasher unit than check that first. Where is it? Every car is different. Here is what I do, first I turn on the hazard switch. You will now hear a clicking sound from under your dash board. (*If you don’t hear a clicking, but more of an audible blinker “sound” then your car most likely does not have replaceable flasher unit. That sound will be coming from a small speaker located in the instrument cluster that is controlled by a computer) (*in some cars the flasher unit is built into the HAZARD switch itself, feel the switch. Do you feel it clicking?) After verifying your car does not use either of these flashers, reach up under the dash and start feeling around. The clicking will be accompanied by a tapping that can be felt in the sub frame of the dash.  It will be noticeable but may be hard to locate. If this is the case you may need to remove the lower dash covering to access the flasher unit. The flasher will usually look like the picture above, however there are quite a few variations. Once you locate the flasher unplug it. The hazard lights should stop working, if they continue you have the wrong part. Reinstall it and continue the search.

After you find the flasher unit you need to note how many contacts it has. Some have 2, or 3. Others have 5, or 8. You need to know this so you can compare them to the parts we have listed on our website. Like I mentioned before we really don’t know what part will work in every car, only the cars that we have worked on. So compare yours to what we have available and see if we have a match. Note I said this is the easiest route, even though it sounds like quite the project. That process should take a novice DIY’er about 30-40 minutes to get done. It is fairly easy to do on most cars, and is plug-n-play.

Option 2 requires some tools to get it done. This option is for cars where you cannot replace the flasher or we do not offer a replacement for it. Now that we understand how the flasher unit works we can trick it. The trick is to put the original load back on the flasher unit. We have Load Resistors to allow us to do that.

We have 2 choices of resistors, a 6 OHM and a 3 OHM. Which one do you use? The 6 OHM is the equivalent load of 1 bulb. So if you replace 1 set of bulbs, (the front OR rear bulbs) you will need to install 1 pair of resistors. The 3 OHM is the equivalent load of 2 bulbs.  If you replace all 4 of your bulbs than use 1 set of 3 OHM resistors.

Where do I install them? The resistors need to be installed to the wiring of the bulb at the light socket. We supply splice taps for a painless installation. Below is a video on how these connections work, note my awesome hand modeling skills!

Find a suitable location away from any heat sensitive materials on your car like plastic or wiring harnesses and mount the load resistor. If you are using the 3 OHM load resistors you can make the connection at the front OR rear turn signal wires.

Things to note about this option are: Load Resistors are sold in pairs. One for the Left blinker circuit and one for the Right blinker circuit. Some cars monitor all 4 bulbs separately, if this is the case with your car you will need 2 sets of 6 OHM resistors. Some cars use more than 4 bulbs as blinkers. An example is the new Dodge Challenger. It uses a total of 4 bulbs in the rear and 2 up front. This increases the wattage of the blinker circuit and needs a larger amount of load to correct the Hyper-Flashing. In that car we used 1 set of 3 OHM resistors in the rear and 1 set of 6 OHM resistors  in the front as it monitors all 4 blinker circuits independently too.

I hope this was informative and helpful. If you feel that I left something out or have more questions leave a comment. You can also email me directly here: tech@v-leds.com and  I will answer any other questions that you may have.

Thanks for reading,

James, the tech@v-leds.com