Question about upgrading headlights to H4 bulbs

JimNH

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While I have some time to spend on the Jeep over this weird time in everyone's lives, I am hoping to work on the lighting issues. Yes, the stock units are very dim. But though I have read a bunch of posts, I still haven't definitively answered this - can you put H4 bulbs into the stock housings/lenses? My plan is to build a battery-direct harness with relays and put better bulbs (Silverstar Ultras or some such) in the stock units. Not willing to afford LED's just yet, plus I am not sure my wife would like the look. I purchased some harness making materials, and bought H4 connectors vs. H13 - but I can wire it up either way depending on what is needful. I have read that there are more choices in brighter bulbs with H4 connectors than with the H13's.

Another question - if I am going with standard Halogen lights (not LED's) can I omit the capacitor and diode from the wiring harness that powers the lights, or does the Canbus require them?

I also scored a very clean front bumper which I will install (the one that came with the Jeep has a slightly smushed overrider), so I will basically be taking the front of the jeep off.

IMG_3735.jpg
 
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Chris

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No, to my knowledge you can't just replace the bulbs with H4s, you need to actually buy a new housing that is meant for H4 bulbs, such as these ones:

https://www.amazon.com/dp/B00C4AKTM8/?tag=jkforum-20

If you're going with halogen lights, you can indeed omit the capacitor and diode as halogens will not have any issues with the Canbus system.

Great looking JK by the way. I absolutely love the 2-door models.
 
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JimNH

JimNH

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Thanks...My OEM lenses are a bit foggy and pitted, so might just go the H4 route and order these!
 
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JimNH

JimNH

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Here is another dumb question...Why not just throw a fairly inexpensive halogen sealed beam unit into the Jeep vs. the system with a separate bulb and lens?. 7" round is standard and the sealed units should be pretty bright.
 

Oscar-Mike

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$65 for LED in Amazon, not that expensive.
When it's all said and done with the H4, harness assembly and the housing, you may be at $45 ?
 
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JimNH

JimNH

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OH - I would be way over $45. $50ish for the harness and $50 ish for the two lights or bulbs, easy.
 
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JimNH

JimNH

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OK - I broke down and ordered a set of LED head and fog lights on Amazon. When they come in I'll install them and do a review.
 

Ballermaris

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As far as I am concerned LED's are the only way to go whether they are used for on-road or offroad. You will appreciate the difference also if you use LED Tail Lights too. Never really ever have to worry about burn-outs and with brighter outputs, you can just about be seen in the brightest sunlight.

I would recommend that if you do not have the Daylight Running Lights (DRL) activated on the Jeep computer that the function is enabled for safety reasons. The DLRs when used with headlights and not the turn signals or fog lights will be a good way to be seen.

There are different activation selections available, so if you run fog lamps, which are tied into any aftermarket lights as I have on my own Wrangler, they will activate when the DRLs become active after shifting into reverse or even into drive.

For me, in order to have a separate switch to activate the lights mounted on the winch bar, it would take some installation mods to have them rewired to a separate switch, so for the moment, I am going to leave them be considering the situation with Covid-19.
 
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JimNH

JimNH

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No idea if the DLR function is activated - how do I find out? I will have to research this. Can I tie the DLR's to the parking lights as a cheat? Maybe just wire a separate feed from switched power at the fuse box to the DLR's so anytime the car is on they are on? But then how to get the turn signal to work (amber)? I think the amber LED ring for turn signal has to be tied into the marker/turn signal wiring, so having the parking/running light mode light the DLR sounds right. I have read that the LED's don't come with much in the way of instructions, but I am sure there is a Jeep-specific tutorial out there somewhere! Probably on this site if I look hard enough.
 

Chris

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OK - I broke down and ordered a set of LED head and fog lights on Amazon. When they come in I'll install them and do a review.
Cool, I look forward to seeing that!

As far as I am concerned LED's are the only way to go whether they are used for on-road or offroad.
I agree 100%.

No idea if the DLR function is activated - how do I find out? I will have to research this. Can I tie the DLR's to the parking lights as a cheat? Maybe just wire a separate feed from switched power at the fuse box to the DLR's so anytime the car is on they are on? But then how to get the turn signal to work (amber)? I think the amber LED ring for turn signal has to be tied into the marker/turn signal wiring, so having the parking/running light mode light the DLR sounds right. I have read that the LED's don't come with much in the way of instructions, but I am sure there is a Jeep-specific tutorial out there somewhere! Probably on this site if I look hard enough.
Do you have the J-Scan app? If so, you can activate / deactivate the DRL feature with it, it will also tell you in the app if it's currently enabled or not.
 
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JimNH

JimNH

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NO - I don't know what J-Scan is even. A phone app? Do I need an ODB2 scanner? I'll go look it up.
 
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JimNH

JimNH

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Thank you - ordered the VGate Icar Pro scanner from Amazon just now. Awesome!
 
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JimNH

JimNH

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What other things have you done with JScan? Are there some standard/basic things I should do when I get it? This looks like a powerful and fun toy...any advice appreciated.
 
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JimNH

JimNH

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Hmmm...if I use the JScan to turn on the DRL feature, that still does not solve the where do I wire up the halo issue...but I think I have it figured out now.
 

Ballermaris

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Do be VERY, VERY, careful with the tool. You could turn the Wrangler into an expensive paperweight. The HALO will hook into the headlight wiring.

There are a number of settings in the tool that are interesting, including setting the transmission to Tow/Haul for the duration of a tow for example. (It also changes the shift points and will give you some extra 'grunt' power on takeoff.)

The Tow/Haul is for speeds of around 65-70 MPH, no higher. Your RPMs can get off the chain if using the wrong tire size or gear ratio.

The Tool will allow you to properly set the tire size and gear ratio for the Jeep. Many stock Wranglers came out of the factory with 3.21 ratios. If you throw on tall tires, for example, it will throw off the speedo/mileage in a considerable manner and you will soon become fast friends with your local favorite Smoke Bear Trooper.

If you throw on tall tires, you have GOT to change the ratio's in the pumpkins. There are threads with charts for tire size and gear ratios on the forum.

You can use the VIN checker to determine original ratios.

If you have an absurdly older Jeep with tall tires and low mileage, she is likely never been properly programmed. That will make it hard on the transmission too.
 
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JimNH

JimNH

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I have slightly larger tires - 18" rims and 32" tires, IIRC...I will double check. Not too far from stock, but would be neat to see if the data is accurate. Looking forward to playing around, but will be sure to read the instructions so I don't brick my jeep.
 

Chris

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What other things have you done with JScan? Are there some standard/basic things I should do when I get it? This looks like a powerful and fun toy...any advice appreciated.
You can reprogram the speedometer for larger tires, activate the LED headlight feature (so you don't get flickering), and a host of other things. Play around with it, there are so many options.

It's also an OBDII code reader as well.
 

blank

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You can reprogram the speedometer for larger tires, activate the LED headlight feature (so you don't get flickering), and a host of other things. Play around with it, there are so many options.

It's also an OBDII code reader as well.
i saw something on there facebook page not to long ago to also turn on the HID setting. that is to prevent LED "blinking" as they said it. staight from the the jscan facebook page
"
Do you have Jeep JK with aftermarket LED headlights installed? Yes? Do you have problems with blinking? We have solution to that problem.

Go to JScan app and activate set two options to "Active":
- Miscellaneous settings -> LED Quad Headlamps
- Miscellaneous settings -> High Intensity Discharge Lights

When booth options are set to "Active" blinking should be resolved."
 
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JimNH

JimNH

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That's interesting. There are so many posts about flickering LED's and how to resolve it, but I had not ever seen this. I will certainly test it.