Need some assistance from you electrical gurus... - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum

Join Wrangler Forum Today

Thread Tools

Please support our sponsors and let them know you heard about them on
Old 08-21-2013, 04:33 PM   #1
Scott2373's Avatar
Join Date: Mar 2013
Location: Williamson, NY
Posts: 1,203
Need some assistance from you electrical gurus...

I have Truck-Lites. They Flicker. I don't want them to flicker. What size capacitor or in-line doodad can be used to make the flickering stop? I refuse to shell out the ridiculous amount of money they are asking for what I'm asking for. I see it as a product defect and it should be made right by the company, but since that ain't happening...I'm going my own way with it. Yeah, I'm a little upset with this whole issue. Thanks!

2013 Sport in Commando Green
3.73 Gears, A/C, 6-Speed
Scott2373 is offline   Quote Quick Reply
Old 08-21-2013, 04:46 PM   #2
scipio337's Avatar
Join Date: Jul 2012
Posts: 1,381

scipio337 is offline   Quote Quick Reply
Old 08-21-2013, 05:27 PM   #3
bc3_Jeep's Avatar
Join Date: Nov 2010
Location: NE corner of Iowa
Posts: 1,680
Do ALL your lights flicker... or just these?????

The "in line doo dad" you are referring to is probably "correct wiring"..........
"For Gawd's sake, put a RELAY in there or you could burn the whole damn Jeep to the ground" ...this quote brought to you by people who do not understand the law.....Kirchoff's, Ohm's, or Faraday's.
Violation of KISS shall always ring false in TRUE engineering. - ME___
Had 75CJ5, 89YJ, 93YJ. Have 82CJ7 & 95YJ____Not one burnt yet due to lack of relays.
bc3_Jeep is offline   Quote Quick Reply
Old 08-21-2013, 06:26 PM   #4
7ekken's Avatar
Join Date: Feb 2012
Location: South Carolina
Posts: 197
the flicker is caused by pulse-width modulation in the jeep's electrical lighting circuit. this is more noticeable when you change your lights to higher powered ones or brighter ones... or any other light other than a low powered halogen stock bulb. what is basically happening is the voltage on the lighting circuit is fluctuating from anywhere between 7 to 14 volts dc.

the right fix for this is done by either:

1 - purchasing a relay type harness with the proper relays (one for high beams, one for low beams), 2 electrolytic capacitors of at least 220 micro farads in capacitance... wired in parallel of terminals 85 and 86 of each relay (this prevents the relays from chattering and keeps them engaged even if the power drops low for a short moment), diodes of at least 3amps/50volts (to prevent any trace power being sent back to the jeep's pcm/fuse panel the wrong way), and proper gauge wiring and fuses run to the battery to power the new lighting with a steady 12+ volts dc.


2 - making your own harness with the above parts.

these kits are sold pre-made from a few different companies on the web. i purchased some parts from ray at and did everything myself. if you are unfamiliar with electrical wiring, or soldering, or reading an electrical diagram, i would highly recommend buying a pre-made harness.

some people will tell you the diodes and capacitors are not necessary and to just run a few relays fuses and wiring, however, i feel they are a step overlooked by people not understanding electrical circuits in new vehicles where everything is monitored by a central brain or computer unit.

hopefully this helps... feel free to message me with any questions.
2013 JKU Sport Gecko 3.73Auto, Premium Soft Top, Rubi Rails, Ace Rails
7ekken is offline   Quote Quick Reply
Old 08-21-2013, 10:17 PM   #5
WhiskeyMike's Avatar
Join Date: Aug 2012
Location: Austin, TX
Posts: 862
7ekken, thanks for the write up. Followup question, what would cause power to flow back requiring the diodes? The capacitors discharging?
WhiskeyMike is offline   Quote Quick Reply
Old 08-21-2013, 10:40 PM   #6
2resa's Avatar
Join Date: Jun 2012
Posts: 293
2resa is offline   Quote Quick Reply
Old 08-21-2013, 11:53 PM   #7
Scott2373's Avatar
Join Date: Mar 2013
Location: Williamson, NY
Posts: 1,203
Thanks for the specifics! I was originally going to build the harness, then found out Truck-Lite was introducing the adapters. I'm really not keen on the price, especially considering how much the headlights themselves were. I don't have a huge amount of disposable income, but I felt these lights were a necessity given the amount of night driving I do and where I live. I originally read that the flickering only occurred on vehicles with Daytime Running Lights, but since I don't have DRL's and I still get flickering, I'm a little miffed. The flickering will no doubt shorten the life of these lamps. I think that Truck-Lite ought to recall the lights and build the proper circuitry into the lamp assembly. That's just my .02, anyway.
2013 Sport in Commando Green
3.73 Gears, A/C, 6-Speed
Scott2373 is offline   Quote Quick Reply
Old 08-22-2013, 08:35 PM   #8
Shark_13's Avatar
Join Date: Dec 2012
Location: Idaho
Posts: 1,902
Its not a problem with the lights, its the way Jeep designed the newer headlights to work. Pony up for the adapters , build your own, or deal with the flickering. Tons of info about it, so should have been no surprise.

Shark_13 is offline   Quote Quick Reply

Quick Reply

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 03:54 AM.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC. is not in any way associated with the Chrysler Motors LLC