This is the exact same problem I am having!! I am relieved that I am not the only crazy one haha!!!

 

It's a 2002 F-350 Crew Cab Long Bed. I installed the complete LED taillights, and have the replacement bulbs in the front with 18 LED's mounted in aftermarket headlights incorporating 3 LED marker lights per side and Halo rings around the projector low beams and halogen high beams. The cab roof lights are still incandescent, as well as the third brake light.

 

This is strange but I believe that the comment about leakage through the LED module could be correct. Without seeing schematics of the actual bulb it is hard to tell. Remember that an LED is a Diode (the D in LED = Diode). Under normal circumstances a diode only conducts current in one direction (normal circumstances being that the reverse voltage does not exceed the breakdown voltage of the diode). In other words LEDs are polarity sensitive unlike a regular bulb.

A boring old single LED should not cause any reverse flow but I am wondering what these bulb manufacturers are doing for support electronics in the bulb. LEDs do not run at 12V and they have very little tolerance for over voltage conditions. The voltage that a LED requires varies and primarily depends on the wavelength (color of light) they put out. An average red LED needs around 1.8V or so but some colors, like blue, require higher voltages (3V-4V) but they are all well under 12V-13.8V where a vehicle's electrical system runs at. This means they need to install a bunch of support electronics in front of the LED to drop the voltage down and regulate it. They may also put some additional diodes (not light emitting diodes but regular diodes) in front of the LEDs to protect from or handle polarity reversal issues to protect the bulb.

I can certainly think of some circuit designs with a dual brightness LED, such as what would be in turn signal LED that needs two brightness levels to distinguish between parking lights and brake/turn lights, that could cause the parking light wiring to be pulled high when only the turn signal wire has voltage, via the circuity in the LED bulb.

You would think the bulb companies would have designed around this for vehicle use but obviously that is not the case.

I don't think it is a question of the LED not 'drawing' enough but probably 'leakage' from the circuitry frontending the actual LED.

A properly placed resistor, in parallel with the LED, might be enough to bleed this off. Putting a resistor in parallel with the LED effectively adds an additional load to the circuit and bleeds off current in the form of heat. This removes some of the advantages to LEDs as you are increasing the current consumption of the circuit as a whole. A resistor in parallel with the LED should also reduce (or even eliminate) the flasher problems.

Again, without the schematics for the bulb, it is hard to tell exactly what is going on.

What happens when your parking lights are already on? Do they blink or vary at all on the side you do not have the blinkers running on?


I believe the quick flashing problem people have with LEDs is unrelated to this potential leakage issue. The flasher's usually have problems because they are designed for a specific current flow in order to operate properly. Swapping a bulb with a LED drastically reduces the current flowing when the light is supposed to be lit, reducing the heat generated through the heat operated spring in the flasher, and consequently messes up the timing with the flasher. These are old-school current/heat operated devices.

Led Flashers are generally solid state devices with electronic timers (like an old trusty 555) that do not use current/heat to operate and can handle varying loads without variations in the blink rate.

My guess is that the new 2011/2012 SD with the 'Three Blink' flasher does not have these flasher problems but that is just a guess. The fact that it can be automatically limited to 'three blinks' easily tells me that it probably has a 100% electronic flasher and not a heat operated mechanical one.

---Aaron

 

Another followup question that could help. When the parking lights lightly blink with your tail light (when they shouldn't) are they blinking WITH the tail light or alternate to the tail light?

---Aaron

 

That is basically what i was trying to convey from what my dad was saying lol. I'm no electrical engineer but from my understanding off of what you were saying and from what my dad was telling me is that basically by putting the resistors in the right spot then it should stop the fast blink/lighting up when its not suppose to issue because it restores the circuit back to its normal resistance that it originally had with an incandescent bulb.

 

Yah, I am not a huge fan of the resistor idea. I stated it because it could fix the issue. Putting a resistor in parallel with the LED actually reduces the overall resistance of the circuit. I know that sounds strange...how can adding a resistor decrease resistance? Well when in parallel it provides a second path for current to flow and will cause the circuit to consume more current now that here are two paths. Adding a resistor in this fashion to balance the current and make the flasher happy will cause the circuit to use nearly the same amount of current as the old bulb. This removes one of the primary advantages of LED lighting (the others being brightness and long life).



---Aaron

 

Right so the best thing to do to get the full advantage would be to get an electronic flasher from NAPA like Jopache did and stated said in the previous post because then the circuit will run as if it was meant for the LED's with the lower current draw and everything and now you have the full advantage of them.

 

Any electronic flasher did not solve any problems for me but the fast flash (aka the bulb out notification).

Tomorrow I am swapping in a full set of LED tail lights and I will post up results, if this does not work I will start messing around with resistors. I am sure resistors will fix my turn signal issue, but still not sure WHY my front parking lights are lighting up when I step on the brakes!! Maybe i just need resistors on my on my rear brake light circuit as well??

I bought my 3157 bulbs off eBay and they were CHEAP and shipped from China, so maybe that is an issue?? The company V-LEDS is actually about 120 miles away from me and I have been thinking about driving up there and seeing it the guy will stick a couple of his high end turn signals in my truck and if it works 100% then buy them and ditch the CHINA stuff.. The only thing stopping me is that is about $100 in gas for this V10 I got, plus two pair of high end 3157 bulbs is about $100 as well!!

Also as asked above, WITH the parking lights on, no problems are noticeable to the average person, the only thing that is noticeable to someone who knows FORDs is that if I turn the turn signal on rather that just the 3157 front blinker flashing, the corner 194 flashes along with it. It never did that with the standard incandescent bulbs.

 

I would not have expected swapping the flasher out to cure the parking light issue. As I said above I believe they are two separate and distinct issues.

If those are cheaply designed bulbs then it is highly likely the circuitry frontending the LED, inside the bulb assemble, is leaking current out to the parking light wire.

I would be surprised if a high end LED bulb, properly designed for this application, would do that. My belief is that swapping them out with a properly designed bulb would likely cure that problem...as much as spending extra money sucks.

If you decide to do that I would appreciate knowing the results.

---Aaron

 

i agree with aaron the bulbs are most likely the issue, i was just making a guess with he flasher im no electronics guru lol just throwing out what i thought might work but now to me it sounds like the bulbs are most likely the issue.

 

So I installed a set of the full on LED tail lights and it solved the issues with my front parking lights turning on with the brake lights BUT it did not solve the blinker issue (for people that have not read the whole thread, if I turn my right blinker on the left one flashes with it and vice versa, and I do have an electronic flasher relay installed)

 

personally its probably resistors because the full assembly had built in resistors which corrected your problem correct?

 

If it's a wiring diagram for your truck you are looking for, check out this site.

EBSCOhost - world

Username: marshall
Password: public

Courtesy of another poster on FTE.

 

I have not put led's in these trucks before, but i have done conversions on every type of motorcycle possible, both cheapo bulbs, and nice kits.

Every one had resistors, either built in, or seperate that you had to solder in... Some of the chepo bulbs that were purchased came without resistors, and we would go to radio shack and get some to make the flasher work or keep the lights from bleed through illuminating.

The bottom line is, you need resistors to make these lights work properly. They were not designed into the system. In applications where they are designed into a vechicle, there are added resistors where needed.

If you bought cheapo bulbs, add resistors... if you bought a kit they are most likely in the kit already. Just git er done already.

Mark

 

Oh my... I have a 2007 Expedition and I was just thinking in converting the front and rear signals to led's and to buy them at v-led.

Should I rather stick with reverse led, markers, fog lights and forget about the turn signals?

I really dunno how so install resonators or how to locate the flasher.

What is your honest advice?