LED Headlights: Turning on the fogs turns on the high beams, too!, New behavior, fogs worked normally until LED headlights installed. |
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LED Headlights: Turning on the fogs turns on the high beams, too!, New behavior, fogs worked normally until LED headlights installed. |
orthobiz |
Sep 17 2015, 05:26 PM
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#61
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Senior Member Group: Members Posts: 1,754 Joined: 8-January 07 From: Cadillac, Michigan Member No.: 7,438 Region Association: Upper MidWest |
I love my brand new GE Nighthawks. There is no way I could go back to regular headlights. I had a set of sealed beam Hellas.
Last night I turned on the fog lights for the first time and the high beams came on. When I looked at the front of the car, all three were on: the regular lights, high beams AND the fog lights. Any fix for this? I would like to have the fog lights and the low beams on at the same time without the high beams. Edit: up until I installed the LED headlights, turning on the fog lights did NOT turn on the high beams. And turning on the high beams turned OFF the fog lights. In other words, normal behavior. Thanks, Paul |
Matty900 |
Mar 29 2019, 11:19 PM
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#62
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Senior Member Group: Members Posts: 1,269 Joined: 21-February 15 From: Oregon Member No.: 18,454 Region Association: Pacific Northwest |
The issue is the led is not pulling enough load. When you add a resistor it solves the problem. We have them and I tested them to confirm that it solves the problem. I have not had the chance to finalize the install instructions and Bruce has been trying to help me on this. The only questions I have are where is the best place to mount it. One thought is to mount it to the headlight housing on the opposite side of the bar as far away from the metals pop up cover. The reason being, it's a resistor and will get warm. I don't want it next to the paint. The pros of putting it hear is that it is out of sight. The con's if you drive in the rain this can become a wet area so your connections need to be properly weather proofed (good barrel connectors and heat shrink.)
The 2nd photo is only showing you what wires you need to tie in to, not where to do so. However, you can put the wires in here and plug the light in to test and make sure this resolves your issue. Spoke, Chi-town, Mike B where would you suggest mounting this? Attached thumbnail(s) |
Spoke |
Mar 30 2019, 07:46 AM
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#63
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Jerry Group: Members Posts: 6,989 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
...it's a resistor and will get warm. Spoke, Chi-town, Mike B where would you suggest mounting this? Does this go across the high beam or low beam LED? I assume the resistor will have full battery voltage (14V) on it when energized. From the picture it looks like its a 6 ohm, 50W resistor. With a 6 ohm resistor with 14V across it, it will be burning 32W (V*V/R). According to Vishay's TMC0506R000FE02 6 ohm, 50W resistor specs, free air mounting of the resistor allows only 40% of the power dissipation or 20W. To burn 32W reliably the resistor should be mounted on a metal surface like an inner fender likely using the tabs to mount it with screws. A metal brace or bracket might work as well as long as there is solid contact between the brace and the bottom of the resistor. All paint should be scraped off of the brace/bracket/fender for good thermal conduction. This derating in power dissipation in free air is why I ended up with two 12 ohm 50W resistors for the brake light ballast. I started with one 6 ohm 50W resistor but realized this would exceed the manufacturer's recommended free air power dissipation. The resistors for the brake ballast can be tie wrapped onto a brace near the brake MC. Can you use a higher ohm resistor like 12 ohm? If so, then the power dissipation would be 16W and would be consistent with the manufacturer's guidelines for free air mounting. I think you only need to be able to trick the high/low beam switch and provide a low enough resistance to energize the fog light relay. Interestingly these resistors are recommended as ballast resistors for turnsignals when LEDs are used. In this case, they can be used in free air since the turnsignal is on only 1/2 the time thus the overall power dissipation is 32/2 which is less than 20W (40%). |
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