Head lights pulsating at speed.

Chaz · September 02, 2007, 01:09:12 PM

Not sure what this issue is, but going down the freeway, my headlights pulsed. About 1 second intervals or so. (Looked like the head lights on some motorcycles) But at idle, they were fine.
I haven't hooked the start batteries, etc., into my electrical system yet, but will when I get the proper relay. But I want to get this little glitch (at least I hope it is!! $:-\$ ) figured out first.
Any ideas??

Thanx,
Chaz

Jerry Liebler · September 02, 2007, 04:25:03 PM

Chaz,
It sounds like you've got a short in some other circuit and the self resetting breaker of the shorted circuit is causing the pulsing by lowering the system voltage while feeding the short and raising it while the breaker is open. This could be in any of the now abandoned circuits for lavatory or lighting or HVAC.
Regards
Jerry 4107 1120

Chaz · September 02, 2007, 04:39:50 PM

Uh-oh.

Considering how much wiring is cut off.................. not good.

Thanx Jerry.

Chaz

(are pulsing lights a good thing??

)

DrivingMissLazy · September 02, 2007, 05:43:26 PM

There have been many posts in the past about pulsing lights and it appears to be a common problem. I noticed a post recently that MCI had a kit to install to eliminate that problem.
Richard

Chaz · September 02, 2007, 05:51:07 PM

Cool Richard. Do ya have any more info on that by chance??

The odd thing- at least to me -is that it does it at speed. Sitting and idling, it doesn't do it.

I also think I may have a relay or something that needs to be cleaned or replaced. It's supposed to be behind the batteries someplace. I wonder if that has anything to do with it.

Thanx again,
Chaz

TomC · September 02, 2007, 06:53:18 PM

Mine have always pulsed. Put in a exchange 50DN and a new digital regulator-made it much less, but can still see it, mostly at idle. Good Luck, TomC

Len Silva · September 02, 2007, 07:18:17 PM

I'm guessing that because it doesn't do it all the time, it's probably not a breaker tripping. I think that you are running that huge alternator with no real load on it and the regulator is hunting a bit. If you still have the bus blowers, or some other large load, try running that. I'll bet the pulsing stops.

Len

pvcces · September 02, 2007, 09:08:46 PM

Chaz, that is normal with light loads and stock equipment. The stock regulator turns on and off too slowly to prevent pulsing with no load. It will only happen if your battery is not charging very much because it is nearly full up.

If you have one of your factory heating blowers, check how much pulsing you get with that on.

Once you are confident that there is nothing wrong, you will hardly notice it, if it is the typical pulsing.

Good luck.

Tom Caffrey

DrivingMissLazy · September 03, 2007, 05:29:27 AM

Quote from: Chaz on September 02, 2007, 05:51:07 PM
Cool Richard. Do ya have any more info on that by chance??

The odd thing- at least to me -is that it does it at speed. Sitting and idling, it doesn't do it.

I also think I may have a relay or something that needs to be cleaned or replaced. It's supposed to be behind the batteries someplace. I wonder if that has anything to do with it.

Thanx again,
Chaz

One of the regulars on the other board posted three or four links, of which the pulsing lights repair was one of them. Unfortunately I did not copy it and place in the Help board list. Someone else must have seen this. Help please!
Richard

Chaz · September 03, 2007, 06:26:35 AM

Hey thanx guys.
So if something such as a blower (Mine are 86'ed) are turned on or something needs the extra juice such as a battery, it "should" reduce the pulsing? How about when I hook up the start system to the house system and run the AC's. Think that would work?
I just can't do it yet as I need to get a breaker before I make the connection. (500 amp I believe)
But really, at this point, I'd just like to know if I am doing any damage or not. I would just hate to tear something else up as I have plenty of other stuff to do.
If I have to live with pulsing...... ehh, there are worse things.

Thanx again,
Chaz

It just dawned on me that it is allot like when I was holding a welding ground in my left hand and the stinger in my right hand with a welding rod in it and it spun around and caught me in the neck. MAN!!! You talk about pulsing!!!!!!!!

But a helluvalot quicker!!

baker4106 · September 03, 2007, 06:50:36 AM

Mine has always pulsated on my 4106 and they pulsate with the voltage regulator. I can tell by my gen. light on the dash. The previous owner said he never saw it but it happened as I drove it home from his place. Larry 4106

Brian Diehl · September 04, 2007, 07:28:23 AM

I have a 96A3 MCI and it had the pulsing headlight problem. After putting in a new electronic regulator the pulsing was reduced, but not eliminated. At the suggestion of JD @ C&J Coach repair I ran a heavy guage battery wire from the battery directly to the voltage sense terminal on the new regulator. This completely cleared up the pulsing. This may not be your problem, but might be worth a try.

CS · September 04, 2007, 01:31:45 PM

maybe you ought to slow down???