Community Forums

jumblesticks · 10-10-2020, 10:29 PM

With the headlights off it works fine. Turn on the parking or head lights and
1-the turn rear bulb turns on and stays on and with no blink
2-the left side marker light is very dim. Pulling the bulb I measure 6 volt between the 2 bulb contacts and 12V from one to ground and 6V the other to ground.
3-I ground the 6V wire through a 3A fuse and my ammeter. Ammeter shows about 2A going to ground. Lights work mostly ok. Dash turn indicator is dimmer than the other.
4-Checked the relays and found them to be working properly. Moved left and right turn relays around to see if the problem traveled but it did not.

I'm guessing I have a bad ground but don't have any print to look at to help track down ground points

Any ideas out there?

Dennis
Westfield, WI

K7JV · 10-11-2020, 07:03 AM

The six-volt, twelve-volt thing really sounds like two bulbs, or at least two loads of some kind, in series. Is this coach new to you so you've not had the occasion to experience this until now, or did you or someone recently work on some part of the electrical system?

There are some pretty huge design differences when it comes to electrical control systems on these coaches, even though they are made by the same folks in the same plant, so it is highly unlikely that I have any useful schematic information. But hopefully some on this form will be able to spring to your aid, there. A schematic would be extremely helpful, if you are comfortable "reading" one.

But the question of whether work has been done on any of the chassis electrical systems by you or a recent previous owner is the first thing that needs to be asked.

jumblesticks · 10-11-2020, 10:38 PM

I've replaced the front and rear clearance lights with LED ones over the past couple years with no problems and as I look at them it appears they don't care if that 6V wire is grounded or not.

I don't normally drive after dark so it's very real that it's been this way but I just never noticed it. My wife has told me for a couple years now that I had a bulb out in back but now I'm believing she saw the left one (amber) light up and not the right one when I turned on the headlights AFTER checking the turn signals. I believe she thought they BOTH should have lit up but, as turn signals, really neither of them should have lit up. I had a voluntary safety check done at a local diesel shop, they noted a burned out bulb but the series of events were identical to the above with the true problem escaping detection.

I agree on the two bulb scenario as the 2A load my meter measured would be about correct for 2 bulbs (typically). I'm tempted to re-ground both left front and rear left light assemblies and see what happens.

Thanks!

Dennis

K7JV · 10-12-2020, 07:10 AM

Good morning, Dennis. It sounds like you may be onto something. I've changed from incandescent to LED on some of our clearance lights and most all of our interior lights, but not our turn signal "bulbs". I do know that many have had issues with converting those, I think mostly to do with conventional thermal-type flasher devices. Also, while an ohm-meter can be a great tool for testing the existence of and possible operability of an LED device, the actual ohm values are not terribly useful, other than that there should be a very high resistance in one direction, perhaps "infinite", and a far lower value in the other direction.

You might try the grounding idea and see what you get. The 2 amp value seems a bit on the high side for a 12 volt device, particularly an LED device, as that would be 24 watts. I would think that to be quite a bit for an LED lamp, by itself.

But I really do think you are on the right track. We are like you. The fun-factor in driving these beauties is, in my opinion, severely reduced when doing it at night. I just found out that my headlight switch is bad a couple of weeks ago while ferrying our coach to a repair facility before sunrise. We just never use them, so didn't know I had the problem. New switch is now "in hand", so I'll be good to go.

jumblesticks · 10-12-2020, 04:49 PM

Hahahaha! Somebody (previous owner?) crammed a 1076 bulb into a 1157 socket for the left front turn signal! Wasn’t me! And since I rarely drive at night, I never noticed the problem since it only happened with the lights on. Oh well, live and learn! It's all fixed now!

Thanks soo much for your help!!! It's nice to know someone's there and I'm not battling these monsters on my own!

Thanks again!

Dennis