Wiring scematics for 2013 389

Had the exact same problem on an 07 kw. Turned out it was the dash switch. Is it possible it's a loose connection there. Just a thought

 

Ain't got any schematics (and trust me when I say you don't want them either), but look on the firewall to the left of your clutch pedal, there is a little door that pops open (it will pop right off for you too), it exposes the main bussbar and all your relays and circuit breakers, and there is even a trusty handy dandy schematic on the back of the little door showing you the location of every relay, breaker etc. and the size of each.


Could be something as simple as a loose breaker or relay, particularly if wrench holders have been in there to install/switch out stuff. While I love the layout of the new dash, I hate the fact that you pretty much need a special tool to access it. Being as it's new it is likely sumpin simple that hasn't been tightened properly.

 

If you go to this link, there is a link that I posted to a bunch of pete schematics and info.
http://www.thetruckersreport.com/tr...ilt-forum/113177-link-to-pete-schematics.html
If both Clearance and tail circuits are going out , start by looking at the switch, and another place to look is the fog light circuit, some times it triggers the clearance / tail lights. I think most paccar circuits are ground triggered now and can be extra fun to trouble shoot.

 

JayTee makes a good point. I used to run a fleet of gov't surplus Western Star Off Road trucks and they were set up with a 24V system and breakers. Loose breakers were a constant nightmare for us, but once we figured it out, life was good. They all came loose because they were built for pavement, and we about 9 light years from the nearest hard surface, so vibrations were a constant source of amusement for us.