Author Topic: Lighting Issue  (Read 3410 times)

Offline Jay2D2

  • Registered Users
  • *
  • Posts: 114
Lighting Issue
« on: February 06, 2009, 07:26:29 AM »
Ok here's a good one for you guys.

85 C10 with Quad Lights.
When the low beams are on the 2 low lights work
When you hit the high beams the 2 high lights work
However when the highs are on, only one low beam lights.
All lights are good at one time or another just not all at once.

Suggestions?

Offline 69byrd

  • Senior Member
  • ****
  • Posts: 1167
  • Haulin!
Re: Lighting Issue
« Reply #1 on: February 06, 2009, 07:41:42 AM »
Are you sure they are good? Reason I ask is when I put the front back on my truck, I put the lights that came off of it back on it. They had been sitting on a shelf for about 7 months, they worked good when they came off the truck but when I put them back on I had a problem similar to yours. I replaced the lights and they have worked fine ever since.
84 C-10 Stepside       
54 Chevy Truck
Gotta Love Those Stepsides!
http://s493.photobucket.com/albums/rr299/69byrd/?start=all

Offline Jay2D2

  • Registered Users
  • *
  • Posts: 114
Re: Lighting Issue
« Reply #2 on: February 06, 2009, 08:06:09 AM »
Good for sure, he bought 2 new ones plus even switched there sides... always the same side that doesnt work.

I neglected to mention I know of 2 other local trucks that seem to have this problem

Offline frogman68

  • Junior Member
  • ***
  • Posts: 773
Re: Lighting Issue
« Reply #3 on: February 06, 2009, 10:10:44 AM »
Have you verified voltage at the plug sounds like a broke wire..

Offline Jay2D2

  • Registered Users
  • *
  • Posts: 114
Re: Lighting Issue
« Reply #4 on: February 06, 2009, 10:40:13 AM »
hmm i dont think it would be a broken wire, because the low beam will light on low beam, just not on high beam

Offline frogman68

  • Junior Member
  • ***
  • Posts: 773
Re: Lighting Issue
« Reply #5 on: February 06, 2009, 10:46:04 AM »
Dont have a wiring diagram with me but I think the low beam is a dual filament bulb so that when you hit the high beams the higher wattage filament lights, think its a separate wire for that.

Offline Jay2D2

  • Registered Users
  • *
  • Posts: 114
Re: Lighting Issue
« Reply #6 on: February 06, 2009, 11:09:34 AM »
going on memory the light is just a 2 prong
though i could be wrong on that

Offline frogman68

  • Junior Member
  • ***
  • Posts: 773
Re: Lighting Issue
« Reply #7 on: February 06, 2009, 11:24:12 AM »
going on memory the light is just a 2 prong
though i could be wrong on that


 the 2 prong (H4651 / 4651) is the high beam
I am thinking that the (h4652 / 4652) is a 3 prong that is the low beam.

Offline Jay2D2

  • Registered Users
  • *
  • Posts: 114
Re: Lighting Issue
« Reply #8 on: February 06, 2009, 11:27:13 AM »
it is possible

have to go look tonight

Offline frogman68

  • Junior Member
  • ***
  • Posts: 773
Re: Lighting Issue
« Reply #9 on: February 06, 2009, 11:31:33 AM »

Offline farmallgray

  • Newbie
  • Posts: 89
Re: Lighting Issue
« Reply #10 on: February 06, 2009, 02:41:04 PM »
The low beam bulbs have two filaments. I would say the low beam filament in one of your low beam bulbs is burned out.
You either need a 4652 (non halogen) or an H4656 (halogen) low beam replacement.

Under edit; I see you said you tried new bulbs. In that case I vote for a bad connection and keep in mind that they are a 3 prong bulb so it is possible that they light on high but not low.
« Last Edit: February 06, 2009, 02:48:02 PM by farmallgray »
1979 K-20 350/TH400

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 17824
Re: Lighting Issue
« Reply #11 on: February 06, 2009, 04:06:05 PM »
The low beam is a dual filament bulb. Check your connections and or the bulb.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)