Author Topic: Tail Light Burnout Problem  (Read 6941 times)

Offline movie cop

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Tail Light Burnout Problem
« on: August 07, 2010, 10:49:23 PM »
I have an 85 Prevost that keeps burning out the tail lights on the right side only. I have replaced the old corroded receptacles and all visible wiring; however the new bulbs glow extremely bright for a few minutes before blowing out (making me think that that there is a short in the line somewhere). I'm looking for a fix that won't involve having to go through the "miles" of hidden wires, maybe something like an in-line voltage regulator or something of that nature. Thanks for any advice. John

Offline stevet903

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Re: Tail Light Burnout Problem
« Reply #1 on: August 08, 2010, 05:27:44 AM »
Check the voltage at the bulb connector.  It should be around 24V with the engine not running to 28V with it running.  If the voltage regulator is set too high, you would likely be boiling your batteries and burning out all of the lights.  Check the bulbs - maybe you have 12V bulbs in a 24V system.

Steve

Offline robertglines1

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Re: Tail Light Burnout Problem
« Reply #2 on: August 08, 2010, 06:24:18 AM »
My 89 prevost uses 24 volt light bulbs in rear and clearance/marker lights..Bob
Bob@Judy  98 XLE prevost with 3 slides --Home done---last one! SW INdiana

Offline JackConrad

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Re: Tail Light Burnout Problem
« Reply #3 on: August 08, 2010, 08:05:31 AM »
Sounds like an over-voltage issue rather thaqn a short. A short should cause a breaker to trip or a fuse to blow. Over-voltage could be due to alternator output too high or 12 volt bulb in a 24 volt circuit.  Jack
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Offline scanzel

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Re: Tail Light Burnout Problem
« Reply #4 on: August 08, 2010, 09:46:12 AM »
Extremely bright sounds like a 12v bulb in a 24v circuit. What is the number on the bulb bases?
Steve Canzellarini
Berlin, CT
1989 Prevost XL

Offline gus

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Re: Tail Light Burnout Problem
« Reply #5 on: August 08, 2010, 04:53:36 PM »
That is what 12v bulbs do when wired to 24v!!
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Offline movie cop

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Re: Tail Light Burnout Problem
« Reply #6 on: August 09, 2010, 11:00:47 AM »
 :o Thanks everyone... the 24v bulbs should resolve the issue... newby to bus thing can't ya tell?

Offline robertglines1

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Re: Tail Light Burnout Problem
« Reply #7 on: August 09, 2010, 11:23:29 AM »
jump in no stupid questions except ones not ask!
Bob@Judy  98 XLE prevost with 3 slides --Home done---last one! SW INdiana

Offline Jriddle

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Re: Tail Light Burnout Problem
« Reply #8 on: August 09, 2010, 01:13:46 PM »
It's kind of like having the rear OFF switch in OFF POSTION and wondering Why bus will not stay running. Makes one feel a little dumb but I always hope when I ask questions that are easy and or dumb to me, that someone else gets help for the same problem but was scared to ask. Keep asking that is how we all learn

John
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Offline Lin

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Re: Tail Light Burnout Problem
« Reply #9 on: August 09, 2010, 01:18:05 PM »
BTW, when looking for 24 volt bulbs, Napa sometimes has them listed as 28 volt.  An inexperienced counter person might tell you they do not have 24's.
You don't have to believe everything you think.

Offline eddiepotts

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Re: Tail Light Burnout Problem
« Reply #10 on: August 09, 2010, 08:34:42 PM »
Thats some good info Lin. Thanks

Offline bigjohnkub

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Re: Tail Light Burnout Problem
« Reply #11 on: August 11, 2010, 10:22:52 AM »
Just a suggestion. Go to your local starter repair place and see if they can order a box (or boxes) of bulbs for you in 24v. NAPA and others are very proud of there probucts. I paid .50 for each bulb.
  big john
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Offline steve wardwell

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Re: Tail Light Burnout Problem
« Reply #12 on: August 11, 2010, 11:17:41 AM »
Granger supply also a good source for muffin fans on and on
Sometimes the more I think about something the less I think about something.    As soon as I save a little money my bus finds out.                                      Why grab a plane when you can take the bus ?                         If I'm wrong 10% of the time how can the "Queen" be right 100%