96 1500 running lights switch problem

I have a 1996 c/k 1500 that used to be a Mass Highway vehicle. It has daytime running lights.

Recently, the rear taillights stopped working. The brake lights, directionals and reverse lights (and hazards) all still work fine. The fuse and bulb seems fine. Could the switch be bad in the cab ? How do I test it ?

Thanks !

Check and see if your instrument cluster lights work. If they don't
you probably have a blown fuse in the dash fuse panel. My 95
lost the parking lights and dash lights at the same time, and it was
a fuse. Hope this helps

Thanks...actually the gauge lights still work fine, along with the overhead lamp in the cab. All fuses are in good condition too...that's what has me stumped.

Hey guys, I just had the same thing happen to me 3 days ago. Checked fuses all good every light on the truck works fine anyway except for the running lights. Have a 3500 Dually with side running lights and they are out also. Turn, brake, stop, interior, dash, everything works except running. Please help!

If You Are Sure The Under Hood Maxi 60 Amp Fuse Is O.k . Need To Test For Power In To Headlamp Switch (brwn Wire) And Then Power Out ( Yellow ) Wire. If Power In But No Power Out, Replace Headlamp Switch. If Not Replace Multi-function Level Switch ( Also Called Turn Signal/hazzard Switch). Power For Rear Taillmaps Runs Through Both.
Also Most Common Failure Is Rear Taillight Circuit Board. Remove Rear Bulb From Taillamp And Test For Power With Test Light. If Power Is Presnet Replace Tail Lamp Circuit Board . Part # Bk 6802985 From Napa

tking33 go to the back of the truck pull it plug for the tail lights it is on the left side inside the frame get a test light and check for your power on the brown wire.

leemo10
check your drl diode it is knee height it is a black finned 2" by 1 1/2" on the right side the the steering column on the steel tube pull it and check the power on it. you need 10mm wrench and a piar of pliers

All set now !! Found a few shorts under the bed and around the tailgate/hitch. Replaced some wires and now we're good to go. Next project....main seal oil leak. ugghhh.