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Topic: Headlights flickering on and off (Read 287 times) previous topic - next topic

Headlights flickering on and off

Returning home from Alabama last week, it was  after dark and 45 miles from home, my headlights started going off. I would play with the dash switch and the high beam switch and the lights would come back on, this on and off went on for several miles until the rest stop appeared. I got off to the check wires and the switch, I could find no problem and the headlights stayed on at the rest stop and for the remainder of the trip home. We had turned  the inverter on to run the ice maker not long before this problem started and my wife turned it off just before we stopped at the rest area. I don't understand how it affected the lights. I had good voltage and my dash lights never flickered when the headlights went out. Any ideas? After crawling under the front I realized the steering box has a leak so I have a new item to spend money on. If anyone has suggestions on anywhere near ATL where I can get that repaired I will appreciate any and all options. Not sure I have the time or experience to tackle that after checking the posts here on the forum. I'm thankful for this group!
Michael & Roxene, Aussie the wonder dog & his daughter Luna the lunatic.
1993 Grand Villa Unihome 280 build #4203
36' 8.3 Cummins 300 hp- 2001 Chevrolet Tracker toad

Re: Headlights flickering on and off

Reply #1 –
I travel with headlights on for safety. On a recent local trip my wife driving in front in the car noticed the headlights (after about 45 min of driving) were pulsing on-off-on-off.

Long story short, FOT discovered my isolator had bad diodes and needed to be replaced. The alternator was sending 14.6 to 15.7 volts back up through the 12 v system. We also replaced other relays, solenoids, switches, etc that seemed to need replacing/repair. Check your isolator to see if it is "isolating".

Just my recent experience but that headlight pulsing was unique.
Alan & Gerri Ortiz
1996 U295 36 ft.
"Rocinante"
Hartwell, Georgia
1999 Subaru Forester
Build No. 4957 Motorcader 17399

Re: Headlights flickering on and off

Reply #2 –
I would recommend in Atlanta for service work

Alan & Gerri Ortiz
1996 U295 36 ft.
"Rocinante"
Hartwell, Georgia
1999 Subaru Forester
Build No. 4957 Motorcader 17399

Re: Headlights flickering on and off

Reply #3 –
Quote from: craneman –
The headlights are on a separate auto resetting breaker. If there is a short they will go off and on.

Maybe.

But on the 1993 U240, it is all fuses.  Under driver's side of dash.  Visible when dash is flipped up.

Lots of grounds on the far outboard side.

I would start by tightening those and any other connections you can get to.

As I recall there are relays for headlights in the same area.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Headlights flickering on and off

Reply #4 –
Forgot to read the signature. I was referring to later coaches such as ours. Follow Brett's advice.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean