LEDs...

[spacemanspif]

Probably a dead horse, but I didn't want to hi-jack oilpan's thread on amp draw http://ecomodder.com/forum/showthrea...led-32821.html

It got me thinking about regular LEDs and "CANBus" LEDs. So cars "hyperblink" with LEDs installed in lights that are blinkers. The solution for this issue in newer cars is to buy "CANBus" LEDs or a resistor in the supply line to fool the computer into thinking that a regular bulb is installed.

With a 12amp reduction seen in oilpan's thread, would the gains be lost by using a resistor? This is something that I've wondered about for a while but never saw an answer to the question; although I've never really looked that hard either...

I don't care it my car hyperblinks, but I see people on other forums put LEDs in cars using the resistors and how they hope for better MPG or less stress on the alternator, but if the resistor is essentially burning up energy, are there any gains at all?

[oil pan 4]

Most of the savings would be lost through using a resistor.
I don't think you would have to rig up a resistor LED assembly to draw the same amps as a standard bulb, I think you just have to get close to it.

A standard 194 bulb uses about 250ma. A 194LED uses between 10 and 15 ma. Most vehicles with the new computer stuff don't pick up on the 10 to 15 ma as being a load. You may be able to add in a resistor and bring the amp draw up to say 100ma.
But then if the LED goes out the "bulb out" alarm wont signal.

To make the blinkers work normal on my GM truck I switched out the thermal blinker module switch to a heavy duty magnetic blinker module and I left the standard incandescent bulbs in the front blinkers.

In some states the cops will pull some one over if their blinker is blinking too fast.

[brucepick]

I've converted nearly all my exterior lights to LED, but not the blinkers.

First, I recognize that putting a resistor in the circuit (has to be in parallel, not in series) raises the amps draw to nearly what it was with tungsten bulbs. So, not much amps reduction.

And for what?? Unless your blinkers are switched on most of the time, their total current draw is not that much. Of course if your battery is a "starter" type and not a deep cycle, especially if it's on the small side - that would make it more important to reduce amps used by whatever means you can.

My battery that runs my blinkers has about 32AH actually available, and it's not connected to the alternator. No issues from powering blinkers.

[UFO]

You can get a solid state blinker relay that doesn't set its blink rate on the current draw of the bulb. That and the LED blinkers should not change the blink rate and will drop the current of the circuit.

[oil pan 4]

On a lot of domestic vehicles the rear brake and turn signal share the same light bulb filament.
I lucked out and it just so happens the rear tail lights blink correctly being LED.

If I had amber turn signals on all for corners I would do what bruce did and just leave the turn signals all stock for the same reason.
I might add an LED to each rear blinker to make them brighter to help get the attention of drivers behind me who are not paying attention.

The only reason I can think of to convert all the amber the blinkers to LED is if you used the hazards a lot with the engine off.
Which is not something we do very much in the US.

[spacemanspif]

Thanks for the info, it is what I expected. My reasoning for the question was kind-of covered by all of you and reflects the issues I have with my car in particular.
1. I tail, brake and blinker lights are all 1 bulb
2. My blinker is controlled by the GEM (general electronics module) and can't be changed, tuned for, or otherwise adjusted to compensate for the lower amp draw so it's hyperblink or nothing for my Focus
3. If I go rear LED, I'll have hyperblink so I might as well switch the front running/turn signal to LED as well, but at the end of the day I only have 4 bulbs to worry about anyway so is there really any gain to be had in the first place??

[deejaaa]

Originally Posted by spacemanspif

..........only have 4 bulbs to worry about anyway so is there really any gain to be had in the first place??

maybe some probably not enough to measure.

[spacemanspif]

That is what I'm thinking as well. But still plan to switch to LED in pairs as my tail and front running lights burn out and need replacement. Even if it's not an MPG gain, it'll be a benefit to the electrical system in reducing some of the load.

[quagss]

Originally Posted by oil pan 4

Most of the savings would be lost through using a resistor.
I don't think you would have to rig up a resistor LED assembly to draw the same amps as a standard bulb, I think you just have to get close to it.

A standard 194 bulb uses about 250ma. A 194LED uses between 10 and 15 ma. Most vehicles with the new computer stuff don't pick up on the 10 to 15 ma as being a load. You may be able to add in a resistor and bring the amp draw up to say 100ma.
But then if the LED goes out the "bulb out" alarm wont signal.

To make the blinkers work normal on my GM truck I switched out the thermal blinker module switch to a heavy duty magnetic blinker module and I left the standard incandescent bulbs in the front blinkers.

In some states the cops will pull some one over if their blinker is blinking too fast.

In NY they pull you over for any vague vehicle light mod. Be careful.

[oil pan 4]

Originally Posted by quagss

In NY they pull you over for any vague vehicle light mod. Be careful.

That's not just the police state of NY. That describes most of the mid east coast.

I craft my LED mods to look and blink as OE as possible.
Older GM and ford vehicles that use the 2 prong thermal blinker module will blink normally as long as 1 you install a heavy duty magnetic blinker unit and 2 you leave one incandescent bulb per side, up front.

In New Mexico, they don't care. We have idiots here running around with burned out tail lights and blue/purple head lights or blinkers doing the hyper-flash thing from having LEDs installed.