Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Michaeloh59 on December 28, 2016, 07:59:59 pm

Title: Light switch
Post by: Michaeloh59 on December 28, 2016, 07:59:59 pm
Last question for tonite: the most forward overhead light fixture in my 97 U320 is a fluorescent 2 bulb fixture. We have been unable to turn it on. We replaced one of the 2 bulbs with anither we assume to be new, no luck. Is this fixture tied into another overhead fixture? If not then we are at a loss as to where the switch is for this light. Also will the fixture light if only one bulb is good?

Thanks in advance for yalls help.
Title: Re: Light switch
Post by: Bob McGee on December 28, 2016, 08:07:32 pm
Have you tried the switch on the forward end of the cabinet over the copilot' chair?
Title: Re: Light switch
Post by: Barry & Cindy on December 28, 2016, 08:12:38 pm
Do you have electricity at the fixture, could it be the ballast...
Title: Re: Light switch
Post by: Michaeloh59 on December 28, 2016, 09:48:30 pm
Do you have electricity at the fixture, could it be the ballast...
Woudnt know how to check electricity at the ballast.
Title: Re: Light switch
Post by: rbark on December 28, 2016, 11:12:32 pm
Turn on all the light switches you can find and see what happens
Title: Re: Light switch
Post by: Old phart phred on December 28, 2016, 11:58:57 pm
 Pick up a digital volt ohm meter, about 15-20 bucks, learn to use it, and save $10,000 or more in future repairs, tows, etc. Lots of information out on the internet, but maybe a basic electrical course is prudent. No offense intended. Cause your motor coach is a city on wheels. Basic electrical knowledge can probably solve 90% of any electrical issues. For the most part, sparkies are not rocket scientists. Diagnosis all starts at the meter.
Title: Re: Light switch
Post by: TulsaTrent on December 29, 2016, 12:50:38 am
Have you tried the switch on the forward end of the cabinet over the copilot' chair?
That is the correct answer.
 
Trent
Title: Re: Light switch
Post by: FourTravelers on December 29, 2016, 03:14:42 am
Both bulbs need to be good.
Try two known to be good bulbs before spending a lot of money.
Swap them with a working fixture.
Title: Re: Light switch
Post by: turbojack on December 29, 2016, 07:05:32 am
First thing should be get a test light and see if you have 12 volts to the fixture.  When I had fixtures stop working I would just change it out to LED.  My guess is ballast is dead
Title: Re: Light switch
Post by: wolfe10 on December 29, 2016, 08:41:33 am
First thing should be get a test light and see if you have 12 volts to the fixture.  When I had fixtures stop working I would just change it out to LED.  My guess is ballast is dead

Good answer.  If 12 VDC to the fixture and new bulbs did not turn on, it is a ballast.  They can be replaced, or you can convert to LED's.  Assume this is  a "Thinlite" fixture.

My suggestion is to NOT  convert only one of many-- its light will be different than the rest (color and intensity).
Title: Re: Light switch
Post by: KenKetch on December 29, 2016, 11:32:12 pm
When my coach was new to me I thought my front light fixture was not working until someone told me that the light switch was on the front of the overhead cabinet above the stairwell.  I never would have thought to look there and went through the whole routine of checking voltage to the fixture and spending energy thinking about what the problem could be in getting power to the fixture. I was shocked to see it was my mistake about where the switch is located.
Title: Re: Light switch
Post by: Michaeloh59 on December 30, 2016, 06:14:38 pm
Pick up a digital volt ohm meter, about 15-20 bucks, learn to use it, and save $10,000 or more in future repairs, tows, etc. Lots of information out on the internet, but maybe a basic electrical course is prudent. No offense intended. Cause your motor coach is a city on wheels. Basic electrical knowledge can probably solve 90% of any electrical issues. For the most part, sparkies are not rocket scientists. Diagnosis all starts at the meter.

Great minds must think alike, as I was thinking much the same. thanks.
Title: Re: Light switch
Post by: Michaeloh59 on December 30, 2016, 06:17:43 pm
Both bulbs need to be good.
Try two known to be good bulbs before spending a lot of money.
Swap them with a working fixture.
I have not been able to Find another fixture that uses the same bulbs- 18" flourescents IIRC. But I did go buy a few of them and tried two brand new bulbs, just in case both had to be good for the fixture to work. No luck. But it's worth knowing both must work, thanks.
Title: Re: Light switch
Post by: Michaeloh59 on December 30, 2016, 06:22:29 pm
Good answer.  If 12 VDC to the fixture and new bulbs did not turn on, it is a ballast.  They can be replaced, or you can convert to LED's.  Assume this is  a "Thinlite" fixture.

My suggestion is to NOT  convert only one of many-- its light will be different than the rest (color and intensity).
Takes an 18" fluorescent. I thought that meant the fixture was AC. In any case there are either 3 or 4 other fixtures in the galley area that also take fluorescents, though different bulbs. IIRC there is also at least one fluorescent fixture in the head.
Title: Re: Light switch
Post by: wolfe10 on December 30, 2016, 09:38:59 pm
That is the bulb number?  Brand?

There are some "good" brands of these bulbs, and some "we made copies of these bulbs".
Title: Re: Light switch
Post by: Michaeloh59 on December 31, 2016, 04:27:58 pm
That is the bulb number?  Brand?

There are some "good" brands of these bulbs, and some "we made copies of these bulbs".
Brett you are correct the fixture is the thin-lite. I tried two brand new bulbs, GE F15 T8 Garage and Basement, to no avail.
Title: Re: Light switch
Post by: wolfe10 on December 31, 2016, 05:05:55 pm
Identify the correct ballast, then google it for best price: http://www.thinlite.com/

Half an hour labor and a hand full of butt connectors and you are back in business.
Title: Re: Light switch
Post by: George and Steph on January 04, 2017, 04:57:53 pm
Michael,
I was almost exactly where you are last year at this time.  I decided to learn the basics and used Dan Sullivan's work to do so.  Here is a YouTube link for his book.  Don't let the mechanic part intimidate you as it starts very basic.  It is so practical that I purchased the work cards and watched the videos you will see if you go to the link.  It also contains an excellent section on using a voltmeter.

https://m.youtube.com/watch?v=7TQGrWZmvRs

Title: Re: Light switch
Post by: Michaeloh59 on January 06, 2017, 07:35:52 pm
Bought a meter, watched some you tube and put the probes on what i take to be the metal contacts in the fixture. Zip zero nada. Of course that is literally rhe first time i have ever used a meter and perhaps i should try on a battery or something to see what happens. Yea.
Title: Re: Light switch
Post by: FourTravelers on January 07, 2017, 08:44:33 am
Make sure that you have voltage going TO the ballast (primary side) the contacts where the lamps plug in are on the load side (secondary side) If you have voltage at the ballast AND two new lamps the you can be reasonably sure the ballast is bad.
There is a chance that a wire has pulled loose from a socket or possibly a bad socket (try a new ballast, if not you can always use it as a spare)
Title: Re: Light switch
Post by: FourTravelers on January 07, 2017, 09:08:11 am
Also make sure you match the lamps with the ballast, use proper type lamp for that particular ballast. There should be a label on the ballast indicating the type, size and number of lamps that it can operate.
Title: Re: Light switch
Post by: Michaeloh59 on January 07, 2017, 02:09:20 pm
Make sure that you have voltage going TO the ballast (primary side) the contacts where the lamps plug in are on the load side (secondary side) If you have voltage at the ballast AND two new lamps the you can be reasonably sure the ballast is bad.
There is a chance that a wire has pulled loose from a socket or possibly a bad socket (try a new ballast, if not you can always use it as a spare)

I dont see where to check voltage to the ballast, so im assuming i remove the fixture? Heres anpic of my fixture installed. 
Title: Re: Light switch
Post by: craneman on January 07, 2017, 02:15:51 pm
Squeeze the center cover on the sides and it will come off
Title: Re: Light switch
Post by: Michaeloh59 on January 07, 2017, 03:06:16 pm
Squeeze the center cover on the sides and it will come off
Yea the pic i posted is of the fixture with the defuser cover removed.
Title: Re: Light switch
Post by: drcscruggs on January 07, 2017, 03:48:43 pm
Hello, like someone else posted the switch (for mine) is on the cabinet nearest the door by the AC switch.  I would recommend if you are having problems with the bulbs/ballast and have figured out how to turn on/off that you consider switching to led.  I have put in led strips after removal of the ballast and so far have been happy.  You can get 5 meters of Led off eBay for less than 10 dollars delivered.  Then it is just a matter of putting in 4-6 strips of the leds, soldering them to the + and - (in correct polarity) and you will probably not have to mess with them again. They also require less electricity to put out same light.  Just my thoughts.  I have changed pretty much all of my incandesent and flourescent lights out to LEDs and am pleased.  Best of travels. 
Title: Re: Light switch
Post by: craneman on January 07, 2017, 04:13:54 pm
Yea the pic i posted is of the fixture with the defuser cover removed.

The white center piece in your picture will come out by squeezing it also
Title: Re: Light switch
Post by: FourTravelers on January 08, 2017, 05:22:27 am
Craneman is correct....... center  metal cover must be removed to expose the ballast, in the same way as the plastic lens
You do not need to remove the fixture to do this
Title: Re: Light switch
Post by: Chuck & Jeannie on January 08, 2017, 08:21:09 am
Here is what the ballast looks like in that Thin-Lite model (after you remove the center metal cover).  You can easily see where the two power leads (the clipped wires) attach to the circuit board.
Title: Re: Light switch
Post by: Chuck & Jeannie on January 08, 2017, 08:28:32 am
If you decide you want to convert that fixture to LED, here is a thread with some photos and ideas (scroll down to Reply #7):

Another (Interior) LED Project (http://www.foreforums.com/index.php?topic=29593.msg251712#msg251712)
Title: Re: Light switch
Post by: Michaeloh59 on January 08, 2017, 03:12:01 pm
Here is what the ballast looks like in that Thin-Lite model (after you remove the center metal cover).  You can easily see where the two power leads (the clipped wires) attach to the circuit board.
Pulled off that metal cover and tried to take a reading from the power leads where they are attached to circuit board. Not sure i had enough naked wire exposed but i did get a very small reading, .04 and jumping around a little. But when i turned off the light switch the meter drops to 0. Turn the switch back on and back to .04. I thought it should be 12V but then i dont know much, and it may be that there was not enough exposed wire to get a good reading. In any caee it would appear that i am getting power to the ballast but no powerr from the ballast. So bad ballast, right?
Title: Re: Light switch
Post by: Mike Leary (RIP) on January 08, 2017, 03:39:44 pm
As long as you replaced both bulbs with el cheapo made in China by GE (the only ones available here) and no light, then it is your ballast, which generally don't go out. That being said, my neighbor with his Wanderlodge had one of his banks just go out, had him get fresh bulbs, nope. We pulled the fixture and could see where one of the wires on the ballast had fried. He's going on line, but we did talk about LED replacement, also. Good luck.  ^.^d
Title: Re: Light switch
Post by: wolfe10 on January 08, 2017, 03:46:35 pm
No, you need to verify that you do have 12 VDC to the ballast. .04 DVC means either a bad reading, or something is wrong with the wiring.  You should have a butt connector between house wire and fixture.  insert a pin or other small metal object and get an accurate reading.
Title: Re: Light switch
Post by: Mike Leary (RIP) on January 08, 2017, 04:00:51 pm
No, you need to verify that you do have 12 VDC to the ballast. .04 DVC means either a bad reading, or something is wrong with the wiring.  You should have a butt connector between house wire and fixture.  insert a pin or other small metal object and get an accurate reading.
Which I did on my friend's coach, we had 12VDC to the ballast. I'd find someone who is familiar with a VOM, no offense.  ^.^d
Title: Re: Light switch
Post by: Dick S on January 08, 2017, 04:03:30 pm
Be sure your meter is set for DC Volts, like maybe 20 Vdc setting. The reading you got sounds like the meter might have been on AC Volts.
Title: Re: Light switch
Post by: Michaeloh59 on January 08, 2017, 05:08:42 pm
Be sure your meter is set for DC Volts, like maybe 20 Vdc setting. The reading you got sounds like the meter might have been on AC Volts.

It was set on 20V DC. Double checked it. .04 V
Title: Re: Light switch
Post by: Michaeloh59 on January 08, 2017, 05:13:38 pm
No, you need to verify that you do have 12 VDC to the ballast. .04 DVC means either a bad reading, or something is wrong with the wiring.  You should have a butt connector between house wire and fixture.  insert a pin or other small metal object and get an accurate reading.
Ok. Dont see a butt connector so perhaps i will have to drop the fixture.
Title: Re: Light switch
Post by: Bill Willett on January 08, 2017, 06:48:28 pm
Remove the white section in the center by squeezing it together, the ballast is under it.
Title: Re: Light switch
Post by: FourTravelers on January 08, 2017, 09:37:53 pm
If you are SURE that you are getting a good connection (reading) with the meter and it's only reading .04 V ......
Then check the voltage at the switch. Both to and from (line / load)
Would be best to verify that you have a good ground connection for your meter.
The voltage may be there and you have lost (or at least a poor) ground connection.
Title: Re: Light switch
Post by: Darrel462 on January 08, 2017, 10:30:08 pm
Bought a meter, watched some you tube and put the probes on what i take to be the metal contacts in the fixture. Zip zero nada. Of course that is literally rhe first time i have ever used a meter and perhaps i should try on a battery or something to see what happens. Yea.

Since the meter and checking a circuit is new to you, as you suggested above, were you able to check a known working circuit with the meter so you know what that looks like on your meter. Not saying that the ballast isn't faulty but you need to have faith in your meter and settings.

Good luck,
Darrel