10-09-2014, 01:37 PM
I agree that a ground problem is most likely since they are all tied together at each valve set (front set, back set) on my 93 coach.
The other potential problem would be supply air not getting to the valve set. One way to separate the electrical ground from a air supply problem is to hit the "lower" button for the front and see if those valves work. You could also have someone hold down the "raise" button and then use the tip of a steel screwdriver to feel for magnetism on the tops of the valves (works if you have 6-packs - am not sure about other valve styles). Magnetism equals current flow so if it's there you have an air supply problem.
You didn't mention the "supply" pressure reading so I'm assuming it is normal which suggests air is probably not the problem. On my 93 coach there is a distribution block near the 6-pack for the "supply" air and I believe that is where my "supply" gauge gets its pressure and it is so close to the 6-pack it is unlikely that if the gauge reads normal that there is an air problem.
The other potential problem would be supply air not getting to the valve set. One way to separate the electrical ground from a air supply problem is to hit the "lower" button for the front and see if those valves work. You could also have someone hold down the "raise" button and then use the tip of a steel screwdriver to feel for magnetism on the tops of the valves (works if you have 6-packs - am not sure about other valve styles). Magnetism equals current flow so if it's there you have an air supply problem.
You didn't mention the "supply" pressure reading so I'm assuming it is normal which suggests air is probably not the problem. On my 93 coach there is a distribution block near the 6-pack for the "supply" air and I believe that is where my "supply" gauge gets its pressure and it is so close to the 6-pack it is unlikely that if the gauge reads normal that there is an air problem.
Jon Kabbe
1993 coach 337 with Civic towed