2021 Seneca 37ts front upper marker lights dead/flashing

[JohnRLewis]

Last night my wife noticed while I was following her car in our rig that our front upper marker lights were not working, and every now and then when I hit a bump, they flashed on momentarily.



Clearly a wiring issue somewhere, where should I start to look?

[EA37TS]

Originally Posted by JohnRLewis

Last night my wife noticed while I was following her car in our rig that our front upper marker lights were not working, and every now and then when I hit a bump, they flashed on momentarily.



Clearly a wiring issue somewhere, where should I start to look?

Have the dealer check them under warranty. If you start ripping into things such as wiring it could quickly become your problem and not Jayco's.

BTW, I had one of those clearance lights burned out at purchase and it was replaced by the dealer. The same clearance light is burned out again, one year later.

[Rustynuts]

I agree with taking it in for warranty work, all the front cap light wiring runs in the ceiling and may be difficult to deal with. It might just be a loose plug where the ceiling harness plugs in but that might be difficult to locate. The roof wiring diagram that I have says the Green and white wires that feed the front marker lights are 77.3 feet long!

[rgolding]

Are the clearance lights L.E.D.'s or are the regular incandescent bulbs. Does anyone know of a an L.E.D. replacement?

[75462]

They have a different style with the front and rear cap clearance lights.

Side note, notice the missing clear coat on my front cap from factory. Must have rolled off the line at quitting time on a Friday.

[Rustynuts]

It is possible that you just have a loose ground. Forgot that most all grounds for the coach all run to the back and ground to the frame. Multiple wires are stuffed into a ground lug and are often loose or have come off with a broken screw. We had a screw break once and lost all charging to the batteries as it was the ground for the converter. Anyway most coach grounds run down the frame on the passenger side and connect to the frame up above the trailer hitch, you should see all the white wires. The grounds from the roof come down behind the rear cap, mine are on the passenger side clear in the rear. There is a bundle of about 5-7 wires that ground to the frame, check there to see if everything is tight. I can get a pic later as this reminded me to finish cleaning up my grounds. After the first loss of ground I put a BlueSea bus bar and put heat shrink crimp on terminals on each ground and attached to the bus bar.

[Jagiven]

Originally Posted by Rustynuts

It is possible that you just have a loose ground. Forgot that most all grounds for the coach all run to the back and ground to the frame. Multiple wires are stuffed into a ground lug and are often loose or have come off with a broken screw. We had a screw break once and lost all charging to the batteries as it was the ground for the converter. Anyway most coach grounds run down the frame on the passenger side and connect to the frame up above the trailer hitch, you should see all the white wires. The grounds from the roof come down behind the rear cap, mine are on the passenger side clear in the rear. There is a bundle of about 5-7 wires that ground to the frame, check there to see if everything is tight. I can get a pic later as this reminded me to finish cleaning up my grounds. After the first loss of ground I put a BlueSea bus bar and put heat shrink crimp on terminals on each ground and attached to the bus bar.

X2, really sounds like a ground wire issue! Ground wires tend to cause of vehicle electrical issues. Being it is all the upper marker lights, it will be the main wire connection. Hardest part is determining where the ground wire connects to the frame, but RustyNuts looks like he has you headed in the right direction.

[JohnRLewis]

I was unable to find any loose ground wires, they all looked very secure. The dealer has it now. I'll report back later.

[BIGPAPA1970]

any update?

[JohnRLewis]

Dealer found an issue with the wiring in the upper cap itself. I did not get exact details. The lights have not given me any trouble since.