Posted 9/26/2016 20:47 (#5550607 - in reply to #5550246) Subject: RE: 1989 Mack superliner. Need wiring Diagrahm
S.E. Washington
Does yours have the switch on the dash to interrupt the headlights or markers? On our Mack r series of that vintage that switch will act up and completely kill the headlights. Sometimes a minute working it with contact cleaner will bring the lights back.