Headlight troubleshooting please help
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Headlight troubleshooting please help
Looking for ideas on how to fix my high beam lights. Here's what happens.... lights work great on low beam. When I click on high beam the headlights completely go out. At first, I tried the approach of throwing new parts at it. So far I have replaced the headlight switch in the dash as well as the floor dimmer switch. No luck. Today I measured voltage at the headlight connectors on both sides and I'm getting 12 volts on both the low and high beam terminals when I click the dimmer switch...... which tells me (assuming a proper ground) the high beams should be working.
I pulled up the schematic and noticed that each headlight/front park light/turn signal has its own respective ground terminal at the radiator core support. Now if one of these core support grounds had gone bad you would think it would just affect the side that the bad ground was on. However both of my headlights aren't working on high beam. Ideas? Maybe a grounding issue upstream of the core support?
I pulled up the schematic and noticed that each headlight/front park light/turn signal has its own respective ground terminal at the radiator core support. Now if one of these core support grounds had gone bad you would think it would just affect the side that the bad ground was on. However both of my headlights aren't working on high beam. Ideas? Maybe a grounding issue upstream of the core support?
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So how do the sealed beams work in our trucks? Are there two separate filaments? When low beam is burning and you click high beam, should the low beam continue to burn in addition to the high beam?
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Well both of you guys who responded get the prize.
After all of that troubleshooting it appears both of the high beam bulb filaments had gone bad. Contrary to what I thought, on a 6024 sealed beam bulb, when you select high beams, the low beam filaments go out allowing just the high beam one to burn. I was under the impression that when you select high beams both the low beam and high beam filaments burn together..... which is precisely why I thought it COULDN'T have been a bulb problem. Because my low beams worked great. Lesson learned!
After all of that troubleshooting it appears both of the high beam bulb filaments had gone bad. Contrary to what I thought, on a 6024 sealed beam bulb, when you select high beams, the low beam filaments go out allowing just the high beam one to burn. I was under the impression that when you select high beams both the low beam and high beam filaments burn together..... which is precisely why I thought it COULDN'T have been a bulb problem. Because my low beams worked great. Lesson learned!
More Turbo
Joined: Feb 2018
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From: Oregon
Yep if you look at the schematic its only one set of filaments on at a time.
I actually just fixed one of my front parking lights yesterday where the turn signal worked but the parking light didnt (only the driver side one). The bulb was fine and the connector was fine. I finally tracked it down to what looked like somebody's rewire job where they had connected brown from the parking light, to the white/blue stripe turn signal wire. So ya - that 's not gonna work, that means both filaments get turn signal power and nobody gets constant headlight switch power. So i cut that connection and properly connected it to the main brown, and now the light works properly.
I guess the thing is, you never know what kind of weird wiring job someone else did to the truck in the past
I actually just fixed one of my front parking lights yesterday where the turn signal worked but the parking light didnt (only the driver side one). The bulb was fine and the connector was fine. I finally tracked it down to what looked like somebody's rewire job where they had connected brown from the parking light, to the white/blue stripe turn signal wire. So ya - that 's not gonna work, that means both filaments get turn signal power and nobody gets constant headlight switch power. So i cut that connection and properly connected it to the main brown, and now the light works properly.
I guess the thing is, you never know what kind of weird wiring job someone else did to the truck in the past
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Yep if you look at the schematic its only one set of filaments on at a time.
I actually just fixed one of my front parking lights yesterday where the turn signal worked but the parking light didnt (only the driver side one). The bulb was fine and the connector was fine. I finally tracked it down to what looked like somebody's rewire job where they had connected brown from the parking light, to the white/blue stripe turn signal wire. So ya - that 's not gonna work, that means both filaments get turn signal power and nobody gets constant headlight switch power. So i cut that connection and properly connected it to the main brown, and now the light works properly.
I guess the thing is, you never know what kind of weird wiring job someone else did to the truck in the past
I actually just fixed one of my front parking lights yesterday where the turn signal worked but the parking light didnt (only the driver side one). The bulb was fine and the connector was fine. I finally tracked it down to what looked like somebody's rewire job where they had connected brown from the parking light, to the white/blue stripe turn signal wire. So ya - that 's not gonna work, that means both filaments get turn signal power and nobody gets constant headlight switch power. So i cut that connection and properly connected it to the main brown, and now the light works properly.
I guess the thing is, you never know what kind of weird wiring job someone else did to the truck in the past
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From: Angier, NC
When you were testing for power out at the light plugs you would of had power to only 1 contact at a time with the dimmer switched.
They use to mark the head light bulb packages that bulbs should be replaced in pairs!
Don't they both work at the same time low or high beams? So why would they not burn out at the same time?
Dave ----
ps I had 1 bulb burn out on my 02 Durango and the next day before I had time to get 2 new ones the other side went out.
They use to mark the head light bulb packages that bulbs should be replaced in pairs!
Don't they both work at the same time low or high beams? So why would they not burn out at the same time?
Dave ----
ps I had 1 bulb burn out on my 02 Durango and the next day before I had time to get 2 new ones the other side went out.
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