Front Turn signals don't work when headlights on

[jfp2673]

I have a 2014 Georgetown 351ds and the front turn signals work fine when the headlights are off but as soon as the headlights are turned on the front turn signals turn off. I have checked the wiring harness under the hood and removed the common ground from the frame and cleaned it and reattached it but with the same results. Has anyone had this happen and figured out the cause? Does anyone have a wiring diagram for the headlight circuit?

[Paul S.]

Hope these help. Also, check the front bulbs to make sure the filaments are not shorting out and your grounds for the t signals are good.

[kenandterry]

Loose wiring connections have been found in a variety of Georgetown units that have caused lighting issues and camera issues from time to time.

A standard report is that things seem to operate well until the full lighting system is turned on. You’ll need a multi meter, but you really need to get readings to all your turn indicators front and rear. Some of the lighting.....and this can vary year to year....the bulb is a running light AND a turn indicator, and some are turn indicators only. This means you could have single and dual filament bulbs. Verify that ALL bulbs function properly in both modes. A burnt out bulb can be the source of your troubles.

[jfp2673]

So I removed all of the grounds under the hood and cleaned and reconnected them. Same results. Could be a bad bulb in the turn signals or maybe some replaced them with the wrong bulb. 194 bulbs are in the sockets. Can someone check if that is the correct bulb? I am the second owner and don't have any of the paperwork that came with the motorhome. It could be something that was never wired correctly from manufacture since the previous owner did not make any repairs on the motorhome. I did notice that the cameras work fine if I remove the bulbs from the front markers and if they are in the sockets the cameras wont work if the headlights are on, but work fine if the headlights are off.

[270S]

Originally Posted by Paul S.

Hope these help. Also, check the front bulbs to make sure the filaments are not shorting out and your grounds for the t signals are good.

How did you get to that website - For ford dealers only?

[Paul S.]

I have access through work. I am a heavy truck mechanic for a shipping co. that begins with F.

[270S]

Thanks for the reply. It would be nice if Ford made some items like that available to "educated" end users too - In an open library. It could save them time & $ at times.

[card16]

270S you answered your own question with your comment on time and $, and I am sure that it is their $ that they are more worried about.

[Bluepill]

Sounds like a classic case of a "lost ground" to the turn signals. When a primary ground circuit fails in the "Open Circuit" mode, current will seek other ground paths. In this case, the current may well be "Back Feeding" into the "Hot" side of the headlight bulbs, through the headlight filament, and finally to the headlight ground path. This happens when the headlights have no "Hot" connection turned on. When the headlights are switched on, the turn signal bulb is now connected to "Hot" on both leads, and no current flows.

Long story short, test by running a jumper wire from the turnsignal bulb ground side to a good solid ground somewhere on the vehicle. If you now get proper operation, you have confirmed the problem.

[jfp2673]

Well I found the problem and fixed it. My front side markers were not working even after replacing both bulbs. My front side markers were wired wrong from the factory. The two wires feeding them were a turn signal and park signal wire, No ground wire. So when the the headlights were turned on the two signal wires were shorting out and making me have no front turn signals and the side view cameras were not working correctly. I rewired the side markers with a new ground and everything works correctly now. I cant believe this came from the factory like this and the previous owner never addressed it. Anyway thank you to everyone for all the help.

[kenandterry]

Well here we go again..........

Wiring inconsistencies have been reported here time and time again. Loose wires, bad bulb, no ground.....it always comes back to having to check every bulb under all conditions, and more times than not, the troubles come up when the full lighting system is on. A multi meter is your best tool.

Also.....like the original owner.......there are lots of people that don’t drive at night. Myself included, not because I’m afraid, but I’m retired, and there’s hardly any reason to travel that late into the day. I suspect the original owner didn’t use the full lighting system and was not aware of the problem, or just didn’t invest the time to investigate it.

Glad you got it fixed....another quality control issue remedied by the owner. 👍

[Wolverine 1945]

Sounds like a bad Ground,,, I used to have an old Plymouth Sundance,,, when I turned the heater fan on the speedometer would quilt working !!!
I sold it that way !!!
LOL !!!

[270S]

Originally Posted by Wolverine 1945

Sounds like a bad Ground,,, I used to have an old Plymouth Sundance,,, when I turned the heater fan on the speedometer would quilt working !!!
I sold it that way !!!
LOL !!!

That's not LOL, that's ___. It probably left FR that way.

[Wolverine 1945]

Originally Posted by 270S

That's not LOL, that's ___. It probably left FR that way.

VERY GOOD Possibility !!!