Amp draw before and after LED.
 

1978 to 1991 9th gen chevy/GMC suburban and pickups with the same lighting scheme.

OE running lights draw 3.75 amps.
OE brake lights draw an additional 3.5 amps.
OE halogen low beams soak up 10 amps.
At a stop light after dark sitting there with the brakes pressed the electrical system demands 17 amps.
That's a lot if you are trying to be out driving around with no alternator.

With a mix of mostly LEDs and some incandescent instrumentation and running lights it uses 2 amps (mostly due to OE dash lights I never changed over to LED and the front blinker/running light that I can not switch to LED or my blinkers wont blink)
LED brake lights added an additional 0.5 amps
LED head lights use 2.5 amps.
At a stop light after dark sitting there with brakes pressed the electrical system now demands only 5 amps.
12 amps makes a big difference.

That is significant! Headlights especially.
Arguably taking your foot off the brake and engaging the parking brake would save a little bit extra. :-)

Great information oil pan!

Nice info, thanks for sharing. Agreed, 12A is pretty huge reduction when alternatorless.

lessens the chance of rearenders by keeping them on though.

I could further reduce the running light draw.
The front blinker and running light, a 2 filament #1157 bulb. If I really wanted to I could remove and rewire the front blinker/running light so that the running light function is accomplished with an LED and put something like an #1156 bulb for the actual blinking of the blinker.
I just need something that draws a little more than an amp on one side of the blinker circuit to cycle the blinker module.

Doing this would only save about 0.5 to 1 amp when the running lights are on, hence the reason I have not messed with it.

Also the dash lights. Those are a pain and would only save up to about 1 amp.
Most of them are burned out in my 454 gas suburban so I need to take care of them at some point.

I did similar in my Accord. LED headlights, brake lights (except the center one) and corner lights. Big reduction in amps draw. Thumbs up.

I have been pondering on this with my Civic Hybrid. It is alternatorless, using a dc-dc converter to keep the 12v battery alive. So at night, that is amperage draw pulling off of the hybrid battery, and that is current that is not being utilized to drive the vehicle, requiring more regen. If you think an alternator has draw, you oughta feel what happens to an already underpowered civic when it kicks in full regen. It does make for a nice engine braking effect when decelerating though...
Have you looked at swapping to an LED friendly blinker module? What model Chevy are you working on? I know my 03 Silverado had an electronic module on the back of the fuse block, but GM does have an LED friendly variant available.

As much as I like the economy gain from the few LED's I've put in my car, the dome light swap to LED actually lost me some economy.
As I replaced the 8W uncandescent bulb with a 10W led grid, and did the same with the boot light.

Once at night I needed something from the boot and could not find it in the weak orangy shine of the boot light. I had to use my phone photo light to retrieve what I sought.

I had enough. I ordered some 10 Watt 4x6 SMC LED grids and put them in.
Now you could do brain surgery in the boot. And the dome light is bright enough to not only light up the interior, but also anything surrounding the car. At night I unlock my car from a distance, which fires up the dome light, so it helps me avoid the dog turds in the street ;)

In all honesty I enjoy the LEDs that reduce my economy most :)

I also am a big fan of the LED's in the dome lamps. In the Silverado I used to drive, I swapped out the 194 bulbs in the overhead console map lights for LED units. They were brighter, and sure helped you see things in the cab at night. I don't know if it was the light color, or how the light acted with the "reflector" of the map light, but it also caused much less glare when driving. I considered that a win all around.

I'm a huge LED fan also. Thumbs up for this informative thread!

I like LEDs, as stated, not so for much economy, but heat savings and extra brightness. I have them in the map light and trunk(boot). have no dome light but thinking about putting one in when I redo my headliner, led of course. looking at a stupid bright one I have just for the fun of it.

The heat is a good point. I have been considering taking the tail lights and adding auxiliary running lights, likely 194 incandescent bulbs to keep snow and ice from forming or sticking to the brake light lens.

After driving through some light freezing rain I noticed ice was building up on the head light lenses after I got home.
As far as I could tell it did not effect the light.
But the LEDs do not put off enough heat to clear winter precip off from them selves.
It should not be a problem unless you spend extended time in freezing rain. I was driving for about half an hour and accumulated a very thin layer of ice.


That just gives me an excuse to figure out how to put more lights up front.

I have another one.
This time I am putting a lighted mirror into my suburban.
The mirror is out of a 2000s ford car and replacing the 212 glass tube style bulb with an LED.

The glass tube light bulb part numbers I could find for this bulb were 212, 211, 578 and 6411.

The OEM style lights use around 1 amp each. To run both lights take about 2 amps.
The Sylvania LED I stuck in there was a part number 6411, because that's all I could find at the local parts store. Both lights on at the same time uses 0.05 amps.

Not a huge practical power saver I know. But I do know interior lights are notorious for being left on and killing a vehicles SLI (starting, lights, ignition) battery. If it keeps me from accidently killing my LiFePO4 battery it will be worth the $20 I spent for both LEDs.

So LED savings for this mod is anywhere between 1 amp per bulb to an entire vehicle battery.

Food for thought: in the caddy, when its below freezing and i use the wiper fluid it also sprays the headlights to clean them.

I'm impressed by your 12 amp savings. That would equate to a draw of 1/4th of a horsepower once alternator efficiency was considered.

I just swapped from my standard headlights (in my 1st gen Neon) to the SuperBrightLED headlight ( https://www.superbrightleds.com/more...aid/2215/4995/ ).

With my amp-clamp on at 13.8v, the regular bulbs drew 4.65 amps low beams and 4.8 amps high beams. The LEDs are 1.65a low, 1.85a high. Brightness went up a little to boot. Since I run engine-off a lot and run on the smallest battery I could find (Odyssey PC680-P Battery), it helps a lot.

Overall, I've converted enough over to save about 115 watts with just the headlights on (that's counting the dash lights, tail lights, marker lights, etc.) The gauge cluster LED changeover was notable, as I dropped 20 watts alone there with just the headlights on.

I'm currently working on a new tail section for my car that will use trailer LED lighting that should finally replace my factory tails. I tried a cheaper LED replacement for them at one point, but weren't bright enough. Trailer ones are extremely bright (very directional) and go from 30 watts each to 1.65 watts each when applying the brakes.

Also, I just bought these... http://www.amazon.com/Nilight-Flood-Lights-Bumper-Warranty/dp/B00J5AAX5S/ref=sr_1_3?s=automotive&ie=UTF8&qid=1458221324&sr= 1-3&keywords=nilight and they take about 14-16w, pending voltage (actually drew less power with more voltage...). Great for fog lights or, in my case, reverse lights! About 1/2 the power of my factory tails, but WAY WAY WAY brighter, which is always good for backing up at night.

My biggest advice: You get what you pay for in LEDs. That, and that they are getting better constantly, making it cheaper and brighter every year.

I'm not to convinced on drop-in LED headlight kits. Seems just like the HID kits. They're going into housings made for halogens. Beam pattern is gonna be all over the place and you're probably blinding oncoming traffic.

Unless I'm wrong?

This is the review that made me want to try them...
Group

I can tell you that the pattern is about the same as my old lights. As the review said, these specific lights definitely get right in front of you bright, but not so much in the distance. Definitely what I'm experiencing (though the distance is about the same as old lighting, closer up definitely brighter). I haven't had anybody flash their lights at me so far (only had them for maybe a week and it's not a big area). People around here aren't shy about letting you know, either. My wife's factory xB lights on low beams gets people flicking their headlights at me just about any time I drive at night. All that said, I can definitely see your concern as LEDs are very directional. Time will tell for me with my headlights.

It took a few hours of experimentation to find the perfect orientation of low beam led in halogen housing to get the beam pattern right.
The led high beams were drop in and go.

But you are generally correct. The ignorant and uncaring just drop them in and go.

3 times less electric power, twice the light
 

Hello, All

I have replaced in my Prius 2 phev the standard halogen H4 bulbs with led

The led H4 bulb:
https://priusev.files.wordpress.com/...miled16led.jpg

The patern in low beam, halogen/led:
https://priusev.files.wordpress.com/...croisement.jpg

The patern in high beam, halogen/led:
https://priusev.files.wordpress.com/...inal_route.jpg

The halogen bulb use 61/67 Watts in low/high
The led use 20/20 Watts.

3 times less for more light, estimated twice. The dsc camera use half the time to take the picture with led.

Wow, you even modded the LEDS to make them fit in the lamp house!
https://priusev.files.wordpress.com/...oise.jpg?w=700
Good to know for other Prius owners wanting to do this mod.
Beam pattern looks good too.

I might do something like that to our I10, my wife complains about poor vision from the standard halogens but I'd rather not put overly bright HIDs in reflector housings not designed for it, nor LEDs if their spread is off.
These look like they would work.

The Insight had very poor lighting through its projector lenses with the OEM halogens and do handle my HIDs well without blinding issues, so I keep using those for now. But if the LEDs work well in the I10, who knows.

Thanks for sharing.

Did you take the halogen photos first, and the LED photos later? There is more light from the sky in the halogen photos and less with the LED indicating that either the halogen photos were shot when there was more light out, or the exposure/aperture/sensitivity settings on the camera were different.

I find before/after photos to be inadequate to show relative brightness unless they can be taken with manually controlled settings that hold everything equal. But as you say, it shows the beam pattern which is valuable.

Yes the halogen first.
The camera then receive a little more light for the halogen picture..
So there may be more then 2 times more light between the led / Halogen.

The camera use 1/2,8 aperture for both bulbs; just change the speed.

@RedDevill. Yes I had a problem in my prius because the led-heater have a to big diameter over 51mm.
There where 2 solutions: reduce the diameter or insert a tube. I used the second solution. Easier.

can you post pics of output? also oncoming?

I put LED's for all of my running lights and the lights are brighter with much less power used. LED Headlights getting ordered today. I should easily be only using about 35% of the power used compared to stock. This means driving at night won't drain my battery nearly as quickly and I don't drive at night near as much as daytime :)