2001 western star signal problems

Try checking the ground.

 

Brake and turn signal are on a completely different circuit that never share anything. I think. A wire is touching something. Check areas that get wet or road salt

 

I had this issue on a WS carhauler, and only after heavy rain... turned out one of the trailer light fixtures was not properly sealed and allowing water to get in. Changed out the trailer taillights and it went away. It could also be a ground problem. Start unplugging lights and see if it goes away.

 

Also on an 18 wheeler. If you don't have the heavy duty flasher 20 lamps it will get hot and fail. The ones at AutoZone Advance will not work. I found out.

 

Just joined this website/forum so don't know I'm doing this right, but.......... I have a 2001 WS 4964. Bought it 5 years ago and it looks like about 20 guys got their hands on the wiring under the dash---a real bird's nest. Right from the git go, the left turn signal wouldn't work, especially during a winter start up, until the truck warmed up. Right turn signal and 4 ways always worked ok. Well, we now know that ONE of the problems is that someone connected the GROUND from the low air pressure switch on the right hand side of the brake pedal to the left turn signal. At start up and no air, the air warning circuit was closed and no left turn signal. Once the truck warmed up (90# of air), the warning circuit opened up and the left turn signal worked. Working with a 30 year veteran who wired St Paul Police and Fire units, we cleaned up a bunch of "loose ends", but then the left turn signal didn't work again. Inadvertently, I got it to work by picking up a hot lead(left turn signal) from the column mounted turn signal at the quick disconnect junction. I ran that wire through the firewall and to the NEGATIVE of the left turn signal on the hood, and now it works. Doesn't make any sense, but...........Any body got any ideas? I know there's a whole lot of info left out because of the work of the 20 previous wiring mechanics (bird nest city), but any advice would help. PS Where does one get wiring diagrams for a 2001 WS 4964 VIN 970557 Thanks.

 

You can find wiring diagrams in the body builder section on the website. Not sure how far back they go.