Daytime Running Lights

[saunders1313]

I had somewhat of an electrical question. If I just remove the bulbs from the DRLs is it the same as removing the fuse? I want to get rid of the DRLs and reduce the load on the alternator, would removing the bulbs work?

[ATaylorRacing]

Originally Posted by saunders1313

I had somewhat of an electrical question. If I just remove the bulbs from the DRLs is it the same as removing the fuse? I want to get rid of the DRLs and reduce the load on the alternator, would removing the bulbs work?

I think this would depend on the vehicle....nearly all that I have seen are the headlights themselves, remove them and you have no lights. I found on my 96 Geo Metro that pulling up the E-brake to where it first latches will make them go off, but I can feel the car slow from brake drag....I then grounded the wire that goes to the E-brake and the DRL are disabled, but the headlights work just fine, but now there is the E-brake light on the dash. I might just remove that idiot light because I know when the brake is engaged....the car will not budge. I disable my DRL because when I do EOC then start the motor back up people wonder why I am flashing my lights at them.

[saunders1313]

The lights are different than the headlights. Would it be easier to pull the fuse?

[whitevette]

Originally Posted by ATaylorRacing

I think this would depend on the vehicle....nearly all that I have seen are the headlights themselves,
... I disable my DRL because when I do EOC then start the motor back up people wonder why I am flashing my lights at them.

Do you really care about what other people think about your lights flashing? In 5 seconds ( or less - LOL) they will have forgotten...IF they even notice!

[wagonman76]

Originally Posted by saunders1313

The lights are different than the headlights. Would it be easier to pull the fuse?

It is usually easier to locate the fuse box and pull the fuse, than to get in and remove the bulbs. Id just pull the fuse, as long as its just DRLs that are on that fuse. If there are other things on that fuse, just pull the bulbs. You can check the owners manual to see if there are any other things controlled by that fuse.

[RH77]

Depends on the type -- some DRLs are the bright-beams on a lower current.

I'm not trying to talk you out of it... Um, well OK, I am...

For accident avoidance, I kinda like the idea. It's a minimal load vs. safety, but that's my take. I run headlights 24/7. I just need to figure out how to disable the tails and front markers (8 bulbs vs. 2).

RH77

[wagonman76]

Depends on the type -- some DRLs are the bright-beams on a lower current.

The poster said theirs are their own dedicated bulbs.

For accident avoidance, I kinda like the idea. It's a minimal load vs. safety, but that's my take. I run headlights 24/7. I just need to figure out how to disable the tails and front markers (8 bulbs vs. 2).

If you dont currently have DRLs and run your headlights instead all the time anyway, heres what you can do. Get a 30A relay and fuse from Autozone. Connect the relay coil to the fuel pump lead (usually the switched side of the fuel pump relay or oil pressure switch), and the other side of the coil to ground. Connect the "common" relay terminal to the battery positive terminal through the fuse. Connect the normally open terminal to the low beams. Theyll run whenever the engine is running, and wont be affected when you turn on the rest of your lights for nighttime. I did this on my 6000 wagon, but used the integrated factory fog lights for the DRLs.

[RH77]

Originally Posted by wagonman76

The poster said theirs are their own dedicated bulbs.

Oops -- helps to read the whole post first. I was thinking the Monte was Lumina-based.

If you dont currently have DRLs and run your headlights instead all the time anyway, heres what you can do. Get a 30A relay and fuse from Autozone. Connect the relay coil to the fuel pump lead (usually the switched side of the fuel pump relay or oil pressure switch), and the other side of the coil to ground. Connect the "common" relay terminal to the battery positive terminal through the fuse. Connect the normally open terminal to the low beams. Theyll run whenever the engine is running, and wont be affected when you turn on the rest of your lights for nighttime. I did this on my 6000 wagon, but used the integrated factory fog lights for the DRLs.

The integrated fogs on the 6000 were a nice touch -- it set Pontiac apart from the other GM makes.

I key-off once in a while for EOC, and don't want to "flash my lights" at people as mentioned before. Can you build-in a delay with the 30A/fuel-pump setup? I have a few relays lying around to try it out. The delay would involve some electronics that I haven't tried yet.

RH77

[wagonman76]

Ive never owned a car with factory DRLs (my newest vehicle is a 92 Pontiac Trans Sport van). I have heard about how some vehicles can disable the DRLs with the e-brake switch. So how does that flash the lights? Do they turn on when starting then go off once it realizes the e-brake is on?

Or is more like you want the lights to stay on when EOCing?

The lights wont flash if you just plain start the car. The fuel pump needs to run to get the car started, as well as keep it running. Now if you turn the key to on and leave it there without starting, the lights will come on while the fuel pump primes for a second or so, then go off.

There are delay circuits online, you can build one, then connect it into your power going to the relay coil. Youd have to figure out how much delay you want.

[Sean T.]

With my DRLs, they come on when I turn the key to "on", then flash off while the engine is turning over (to save the battery), then come back on once the key returns to the "on" position.

I would just pull the fuse....

here is a pic of 99 MC headlight for those that haven't seen them before:



You can see there is two headlight areas... can't remember which one is for DRLs.

[RH77]

Originally Posted by wagonman76

There are delay circuits online, you can build one, then connect it into your power going to the relay coil. Youd have to figure out how much delay you want.

The situation would be: key-off to kill the engine, lights-out, then key-on, lights-on. I'll look into the delay circuits.

I'm just curious -- my batt is ancient (6-years). Would it benefit me to just replace it and perhaps save the alternator before Winter hits? It hasn't failed to start yet -- and I've drained it down to 10.9V when parked for storm spotting, radios-on, blower running -- and it started right up (charged to 13V and shut down, repeat) -- I know, off-topic a bit

RH77

[ATaylorRacing]

Originally Posted by wagonman76

Ive never owned a car with factory DRLs (my newest vehicle is a 92 Pontiac Trans Sport van). I have heard about how some vehicles can disable the DRLs with the e-brake switch. So how does that flash the lights? Do they turn on when starting then go off once it realizes the e-brake is on?

Or is more like you want the lights to stay on when EOCing?

The lights wont flash if you just plain start the car. The fuel pump needs to run to get the car started, as well as keep it running. Now if you turn the key to on and leave it there without starting, the lights will come on while ....

On my 96 Geo I have not yet grounded the E-brake wire to shut off the DRLs. Every time I shut the key off they go out, turning the key to the on position does not make them come back on....they will come on as soon as the motor starts running.

[ATaylorRacing]

Originally Posted by whitevette

Do you really care about what other people think about your lights flashing? In 5 seconds ( or less - LOL) they will have forgotten...IF they even notice!

The cop that was in front of me thought I wanted him to pull over, I told him a lie about my lights having an electrical problem that was getting fixed in a shop in a hour since in our state (IN) EOC is illegal. I was following my wife the other day and she thought the same thing. Now I simply drive with my lights on so that when I kill the motor for EOC no one notices because the lights stay on.

Our so called by-pass has red lights every 1/2 to one mile and is near perfect for EOC since as soon as you speed up you need to slow down for the next light and/or traffic.

[wagonman76]

There are other options. You could possibly tap your relay coil power from the ignition module instead, which should have power in both RUN and START positions but be off when the key is off. Then the lights wouldnt go out when starting. Itd do exactly like you described without the flashing. However youd also be running your lights if you need to be parked with ignition on to run your storm spotting gizmos. A DRL switch could take care of that but could be easily forgotten. Or just run the gizmos off constant battery power if theyre not already.

Thats why I like going off the fuel pump. They cant be on unless the engine is running. And I dont EOC. You could run yours off the fuel pump, and put a delay in there and set it for awhile longer than the longest you plan to EOC, then your lights will stay on the whole time and if you care what others think of them, thered be nothing for them to notice.

About your battery, I guess it depends on what kind of cold you expect there and how readily you can get and replace one when it goes. Mine, even when in marginal condition, work great all summer but once it starts getting even mildly cold out, I might as well forget it. I can expect many -20F winter mornings. But Ive got 3 reliable rides plus chargers and jump starters and getting and changing the battery is a cinch. So I milk mine as long as I can.

[RH77]

Originally Posted by wagonman76

There are other options. You could possibly tap your relay coil power from the ignition module instead, which should have power in both RUN and START positions but be off when the key is off. Then the lights wouldnt go out when starting. Itd do exactly like you described without the flashing. However youd also be running your lights if you need to be parked with ignition on to run your storm spotting gizmos. A DRL switch could take care of that but could be easily forgotten. Or just run the gizmos off constant battery power if theyre not already.

Thats why I like going off the fuel pump. They cant be on unless the engine is running. And I dont EOC. You could run yours off the fuel pump, and put a delay in there and set it for awhile longer than the longest you plan to EOC, then your lights will stay on the whole time and if you care what others think of them, thered be nothing for them to notice.

About your battery, I guess it depends on what kind of cold you expect there and how readily you can get and replace one when it goes. Mine, even when in marginal condition, work great all summer but once it starts getting even mildly cold out, I might as well forget it. I can expect many -20F winter mornings. But Ive got 3 reliable rides plus chargers and jump starters and getting and changing the battery is a cinch. So I milk mine as long as I can.

The delay sounds like the best option.

Remember though, that extreme heat tends to kill batts too. This summer has been mild comparatively. I'm just worried that a failing batt will slowly kill the alternator.

I have AAA and an '06 Acura to jump from every other day (carpool free-up), so that's not the biggest concern. I just hear about batts destroying alts, which kill new batts, ad infinitum.

RH77

[bikin' Ed]

There was a post and review on cleanmpg.com about LED replacement bulbs for DRL. They are about $30/ea but could let you have the safety without too much power drain.

As for adding the safety to a non DRL car, you might be able to drill into the reflector housing of a non sealed beam headlight system.

[NiHaoMike]

Those $30 LEDs are overpriced. Here are some for under $8 each:
SparkFun Electronics - Luxeon III LED - White 3 Watt
You'll also need some heatsinks (under $10 each, or free from an old monitor, etc.) and a ballast resistor (under $1).

[orange4boy]

An old battery that does not take a charge properly can rob you of FE as the alt is constantly trying to charge it.

On short trips your battery can become discharged and not have enough time to recharge. This costs gas and shortens battery life as batteries become sulfated when they sit even slightly discharged. The best thing to do is install a battery tender and plug it in when you are parked or get one of those solar trickle chargers.

You could get yourself a deep cycle battery like a yellow top when you replace your existing battery and run alternator free for commutes and medium length trips. Just recharge it at home and connect your alt for long trips.

The reason I found this forum was my alternator belt was squealing when I started every morning trying to recharge my dead battery and my FE sucked. So I looked into running without alt and found the posts here on alt less life. Now I'm getting much better FE and my batteries will pay for themselves pretty soon.
Good luck

[Ford Man]

Originally Posted by orange4boy

An old battery that does not take a charge properly can rob you of FE as the alt is constantly trying to charge it.

On short trips your battery can become discharged and not have enough time to recharge. This costs gas and shortens battery life as batteries become sulfated when they sit even slightly discharged. The best thing to do is install a battery tender and plug it in when you are parked or get one of those solar trickle chargers.

You could get yourself a deep cycle battery like a yellow top when you replace your existing battery and run alternator free for commutes and medium length trips. Just recharge it at home and connect your alt for long trips.

The reason I found this forum was my alternator belt was squealing when I started every morning trying to recharge my dead battery and my FE sucked. So I looked into running without alt and found the posts here on alt less life. Now I'm getting much better FE and my batteries will pay for themselves pretty soon.
Good luck

About how long will a deep cell battery last without being charged if you're using say, lights, heater blower since winter is coming up and windshield wipers in case of rain? Does anyone have any idea?

[orange4boy]

If you have an ammeter in your car you can estimate your battery life by the capacity rating. Example is a Trojan 12v 27tmx with a 175 minute capacity. This battery can provide 25 amps of power for 175 minutes in ideal conditions and down to 100% discharge. You should really only discharge to 50% (12.06V) max for deep cycle batteries. So half that figure is about an hour and a half.

Watts / volts = amps. Amps x volts = watts.

Low beams are typically 55 W each X2 = 105 / 12 = 8.75 amps. The heater fan depends on the setting and the vehicle. Many lights can be replaced with
LEDs which only use a fraction of the power.

From another forum...Don't know the car model but would be good enough to estimate.

I tested at both voltage settings of the alt, where 14.4 is typical alt voltage, and 12.7 is similar to a fully charged battery. The idle current is subtracted out of the other settings.

Idle: 128w @ 14.4v, 89w @ 12.7v
Rev up to 3500 rpm: +35w, (not tested)
Heater fan setting 1: 55w, 38w
Setting 2: 98, 67
Setting 3: 141, 99
Setting 4: 189, 135
Marker lights: 95, 71
Full lights: 240, 179
A/C (heater fan subtracted, but including condenser fan): 163, 114
Defroster: 104, 77
Wipers 1: 48, 38
Wipers 2: 76, 64
Radiator fan: 144, 83

The more current you draw the less capacity your battery can provide.

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