[sciphi]

Good writeup!

Just a few quibbles:

1. A crimp would be much more preferable over a wire nut for attaching the capacitor. Heat-shrink and electrical tape over it, and it'll be far more secure than a wire nut. I have visions of a wire nut loosening on somebody and them losing headlights at the wrong time. A crimp plus heat-shrink has two mechanical means of ensuring the connection stays intact. The wire nut isn't intended to put up with vibration, so it can very easily vibrate off. You mentioned either, and here's the reason why a crimp is recommended over a wire nut.

2. Is there any way of attaching the power feed wires to the battery's positive terminal? That's the absolute best way of attaching those wires since it is getting power directly from the battery. There's more power available there than in the power center.

3. I didn't see fuses mentioned anywhere. Some inline or blade-type fuse holders fitted with 15 amp fuses and attached to each of the power feed wires will prevent a lot of grief if something shorts or a relay welds itself together. Two 20-amp inline/blade fuse holders fitted with 15-amp fuses connected in-line with the power wires will guard your car against fire if anything shorts out. I'd rather not see a crisped Cruze over accidentally omitting $5 worth of fuses. I used the blade-type fuse holders with 15-amp fuses.

I liked the pictures, and liked the writeup. This should make upgrading halogens more accessible to more people!

 

[sciphi]

Those were my only quibbles. Aside from that, it's a great writeup!

I used two fuses, one on each power wire going to each relay.

 

[sciphi]

I'm glad my idea is getting more exposure, and that you ran it down in a form more accessible to folks. :eusa_clap:

For the fuses, one could simply snip the power wires in the middle, put heat-shrink over each end, crimp the fuse holders with butt connectors in the middle of the cut wires, and then seal the crimps with heat-shrink. No soldering needed. And, the crimps pass electricity perfectly fine. Done properly, a crimp can be stronger than the wire.

 

[sciphi]

Heat-shrink is super-easy to use. Get a piece just big enough inside to cover what you want to and long enough to extend a little past it. Slide it over the wire, then make your connection. Slide it over the butt connector or connection, then hit it with a hair dryer. MAPP gas will set it on fire!

I like it for making the connections very corrosion-resistant. And, it's another layer of insurance against shorts or mechanical failure of the connection.

 

[sciphi]

Yeah, its really not that bad. You can practice with some scrap wire before you use it on your own wiring. The trick is being bale to do it with only two hands. You may need to have someone hold the wires for you while you do it.

Radio Shack has a thing that holds the two wires in place for you to do whatever to. I wish I had purchased one, it would have made things much easier. They're about $10, and it'll be handy for other stuff in the future.

 

[sciphi]

Good work!

Did you get fuses and a capacitor in there? The low beam relay will be unhappy with the DRL if there's no capacitor.

 

[sciphi]

I had thought maybe I lost the DRL functionality after the upgrade. While during my drive to work this morning my full headlights were on. Half way there there was enough light to kick the headlights off and DRLs came on. :eusa_clap: My buddy was impressed with the lights and he runs plug n play HID setups on multiple cars.

Success!

Keeping the DRL while making the headlights brighter is the win-win for this mod. By keeping the factory DRL functionality, it's the only lighting mod that's legal everywhere in North America.

While the lights are now putting out about half the lumens of a PNP HID kit, it's focused properly onto the road. If you've ever ducked down below the cutoff in front of the Cruze after doing this mod, the headlights are blindingly bright. The cutoff really does its job protecting oncoming drivers while allowing the low beams to throw enough light to drive safely at 55-60 mph on a 2-lane road.

 

[sciphi]

When I do this upgrade I plan on upgrading the bulbs to Philips Xtreme Vision bulbs. I believe these are the brightest clear glass halogen bulbs out there and combined with the wiring upgrade should really brighten up the road.

Just be careful you're not killing expensive bulbs prematurely. The reason I went with a moderately-priced bulb is that I wanted to get some kind of lifespan out of the headlights. I'm coming up on 5 months with the Sylvania XtraVisions, and they're still working fine.

 

[sciphi]

Update for those running Sylvania XtraVision H13's along with a harness: My driver's side XV burned out after about 5 months of constant use. It was replaced with a plain Philips H13 bulb. The passenger side will likely burn out sometime soon.

 

[sciphi]

ok need some felp form you smart people....just did this tonight with a friend and we are not alble to turn the headlights off with the switch. for example when the car is running i cannot turn the headlights off....the tail lights and parking lights do but not the headlights, even when i turn the car off.......any ideas, is something wired wrong? or is that just how it is because it is getting power from the battery??
THanks Ryan

The headlights should go off with the car off, or when the switch is turned all the way to the left. Check the exterior lighting settings, as when it's dark out the car lights up like a firework for 30 or more seconds to let one see when they're approaching/departing the car. If your headlights don't go off, then see below.

My harnessed headlights go off when the car turns off. Could be a bad relay stuck open. If they only shut off when the relay is physically removed, then the relay itself is bad. Replace with another relay, and it should operate properly.

 

[sciphi]

Sounds like a bad capacitor, or that it was installed incorrectly. There should have been arrows on the capacitor if it was one-directional. Search on what way to install it, as most capacitors hate being installed the wrong way.

 

[sciphi]

The arrows on mine looked more like >>>>> than regular arrows. They also had a + and a - to designate which end went where. + would be the power feed wire, while - would be the ground wire.

It's also possible you had it wired across two different terminals, or something shifted after installation.

Xtreme, is there a picture of your capacitor, and where to install it? My harness uses a different relay than your harness.

 

[sciphi]

Just a note to people who feel it's necessary to install in-line fuse holders in this harness. From what I can see it's a needless expense and addition of connectors to a very nice harness. I got my harness yesterday and took it out to look it over today( it actually got here before my car!). It's a well built harness, much better than most relay harnesses I've seen in the past. I got to thinking that even the cheapest harness I've bought in the past included a fuse holder for circuit protection, yet this very nice harness didn't. After closer examination of the harness, I discovered that the 2 black wires that plug to the red wires for power supply are actually labled as fusable links. I was curious as to why they were black yet plugged into the red power wires. Now I know why. I won't be putting online fuse holders on mine as there's no need to fuse a fusable link.

Nice find! Glad to hear my concerns about it not having fuses were unfounded!

 

[sciphi]

Only time will tell as Sciphi was one of the first to do this mod. His was a custom made harness not the one that was bought. Obviously it will matter on how much you drive as well. I maybe only drive 8000 miles a year so results will also vary in that regard.

I was the first to do this mod, and made my own harness. Xtreme did a great job of finding a reasonably-priced harness that works well, and writing it up to make it more accessible to more folks.

My driver's side XtraVision burned out after about 5 months and ~9000 miles of use. I drive a lot for work, so the miles pile on quickly. The XV bulb in the passenger side is doing fine. I'll update when it finally goes.

The great thing about the harness is that it works just as well with the OEM bulbs as the high-priced "performance" bulbs. Basically, it'll turn a regular bulb into a "high-performance" bulb through the magic of physics. So, one can walk into a parts store, grab a cheap bulb off the shelf, and expect amazing results with it plugged into the harness. The regular bulb should last longer while providing the same results as a very expensive bulb. There are many reasons for this, including that the expensive "high-performance" bulbs are built for lots of light instead of lots of life. So, a regular bulb with average light output (without a harness) and average life can be expected to do the same, while living longer.

FWIW, I can't tell a difference between my "regular" replacement and the still-living XtraVision. The regular bulb is in fact better in some ways, such as lighting to the sides.

With bulb life, yes, the low beams are on at all times. Don't forget, this car has a variable-output alternator. Most of the time when the car is driving in the daytime the headlights will be getting the 12.5 volts needed to run the car. At night, the car tells the alternator to put out 14 volts to ensure proper voltage to run the headlights and other exterior lights. Bulb life has to do with voltage put through the bulb, among other things. Running at 12.5 volts during the day will make the bulb live longer than if it were running at 14 volts all the time.

Moral: Try the harness on the OEM bulbs first. Then, if not satisfied, get plain-Jane replacement bulbs.

 

[sciphi]

Glad to help! And, glad to share insights learned along the way! "I see farther because I stand on the shoulders of giants".

 

[sciphi]

I officially got 6 months from the Sylvania XtraVisions running full-time. The passenger side blew yesterday, and I threw in an OEM bulb (Sylvania, BTW) I'd kept for just this eventuality. Another Philips H13 was picked up today. I'm hoping the Philips bulbs last longer than 6 months. Remind me to swear off anything Sylvania-branded in the future. The Philips bulb had a much more even light than the OEM Sylvania. I've gotten disappointed by Sylvania too many times now.

 

[sciphi]

I've never had DIC problems. Were your regular analog gauges working okay?

 

[sciphi]

That's a pretty-looking harness! Enjoy, and hope it goes smoothly for you!

 

[sciphi]

True, the alternator varies voltage output, but this voltage change is to keep the battery's state of charge at the correct level. It has nothing to do with making the headlights brighter at night. Voltage will vary slightly with different levels of electrical load, but this has much to do with the fact that the voltage displayed at the DIC is affected by the loads running along it's shared circuits, all of which are affected by the resistance (and voltage drop) along the wiring harnesses. If you were to measure the voltage directly at the alternator output you would see that the voltage changes very little with varying loads (full lights, rear defrost, seat heaters, etc.)

The OEM DRL system uses a PWM (Pulse Width Modulated) driver to lower the power level of the headlights during daytime driving. At night when full lamp power is required the PWM driver is not engaged and full supply voltage is used to drive the bulb.

...

Has anyone actually measured the voltage difference between the headlight connector and the positive post that this harness connects to? That voltage delta, minus the resistance in the wiring of the upgraded harness, will tell you exactly how much more power we can supply to the OEM lights.

Another thought on this: running around with the low beam lights on full intensity all the time (instead of using the PWM DRL signal) will be what burns the bulbs out far quicker. Not only that, but bulbs burn for far longer if they are not turned on and off as often - the thermal shock wears out the filament faster - so every time you switch your ignition on, even during the day, the bulbs fire up at full intensity. These two factors will result in dramatically reduced bulb life, even with OEM bulbs. I'm not saying this mod is not a good idea because of this, I'm just saying that people should be aware that their bulbs will burn out faster even when sticking with OEM bulbs.

I'm no electrical engineer, nor do I play one on TV. I do know how to observe, report my observations, and form a reason for the observed behavior, though!

I was reporting what I had observed, and reasoning why. During the day the car runs at 12.5 volts, and at night with the headlights and exterior lights on it runs at 14 volts. I've verified that both through the DIC and through a scanner. Likely my reasoning was wrong, seeing how I'm a hobbyist, and not a professional EE like some friends of mine are. However, based on observed behavior, I had what I thought was a likely reason.

Xtreme, update in a month or two. I got ~5-6 months out of the XV's before they stopped working. Then again, I drive quite a bit, and have many startups during the day.

 

[sciphi]

I'm no electrical engineer, nor do I play one on TV. I do know how to observe, report my observations, and form a reason for the observed behavior, though!

I was reporting what I had observed, and reasoning why. During the day the car runs at 12.5 volts, and at night with the headlights and exterior lights on it runs at 14 volts. I've verified that both through the DIC and through a scanner. Likely my reasoning was wrong, seeing how I'm a hobbyist, and not a professional EE like some friends of mine are. However, based on observed behavior, I had what I thought was a likely reason.

Xtreme, update in a month or two. I got ~5-6 months out of the XV's before they stopped working. Then again, I drive quite a bit, and have many startups during the day.

You stated the below information as though it was a fact:



I don't like the idea of people posting information that's not factual, that's all. "Forming a reason based on observed behaviour" is likely how most internet sourced mis-information begins.

Thanks CUDA for posting those links. Any un-regulated circuits/systems in the car will use over 11% more power running at 14.4V vs. 12.8V, so it's not surprising to see the OEMs are all over that as a source of fuel savings. Not to mention the additional benefits of reduced wear and tear on the battery.

The complexity of this voltage regulation system makes me wonder about the implications of upgrading the "Big 3" wiring systems (alt-bat, bat-gnd, engine-gnd). Bypassing the inline current sensing devices will likely reduce the percieved usage current and may lead to an under charged battery? I will be doing further investigation before upgrading any of my vehicle's main power wiring.

As I said, I'm reporting what I observed. And at least on my Cruze, during the day the voltage is 12.5 volts, and at night it's 14 volts. I fail to see how that's not factual. I also don't appreciate being called a liar. If you'd like, I can post pictures that back me up.

Take it with a grain of salt because without reading verbal cues I'm assuming you elegantly called me a liar, but the harness I made keeps the DRL on at full power whenever the car is on and calling for the DRL to be on. It operates just like the factory harness since it's using the factory harness inputs, including DRL inputs, to control the relays that power the lights.

I'm not attempting to trick or deceive anybody with my posts, especially ones that can be fact-checked by any Cruze owner. I do my best to be as correct and truthful as possible. I may not always have correct information, and I admit that. Being incorrect doesn't make me a liar, it means I'm not correct. We're all here to learn. If I've reported incorrect information and can be proven that it's incorrect, then I'll admit my mistake and learn from it.