phildirt Posted May 20 Share Posted May 20 (edited) My truck has no brake lights when stepping on the service brake pedal. The turn signals work (and 4 way flashers). The blue tractor brake button activates the brake lights, the yellow maxi brake yellow button also activates the brake lights. All of the lights - marker, service brake and turn signals lights work thru the trailer connection. New trailer lights air switch, new Signal Stat turn signal switch. The wiring diagram for the truck shows a "service stop light switch". Anybody know where I can find where that switch is physically located? It is not the one located under the floor pan to the rear of the primary fuel filter. Any help?? Edited May 20 by phildirt Quote Link to comment https://www.bigmacktrucks.com/topic/74172-rw-613-superliner-ii-tractor-service-brake-lights/ Share on other sites More sharing options...
mechohaulic Posted May 21 Share Posted May 21 can't guarantee location; did you look on the treadle (foot brake )valve? if you have a blue / yellow red knobs on the dash, the blue should be a "master control" valve. which is why brake lights work same with blue or yellow. Quote Link to comment https://www.bigmacktrucks.com/topic/74172-rw-613-superliner-ii-tractor-service-brake-lights/#findComment-552135 Share on other sites More sharing options...
mechohaulic Posted May 21 Share Posted May 21 going to work tues (tomorrow) I will be going by two supers which I took pictures of the steering boxes( for another post) .will stop to check the situation. Quote Link to comment https://www.bigmacktrucks.com/topic/74172-rw-613-superliner-ii-tractor-service-brake-lights/#findComment-552136 Share on other sites More sharing options...
Joey Mack Posted May 21 Share Posted May 21 On the firewall behind the rear head.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74172-rw-613-superliner-ii-tractor-service-brake-lights/#findComment-552142 Share on other sites More sharing options...
phildirt Posted May 23 Author Share Posted May 23 Fixed. It was a combination of a bad air switch (the one behind the primary fuel filter on the treadle valve) and an open circuit between the two brake controls on the dash (maxi and tractor parking brake buttons). Thanks for the suggestions and to Josh. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74172-rw-613-superliner-ii-tractor-service-brake-lights/#findComment-552382 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.