[Richard]

The next thing I would try is very simple, but will tell you if the HWH is working or not in travel mode. You said the travel solenoids are magnetized, so the following is a simple sanity check.

Crawl between the tag and the drive tire, find the connection point on top of the rear axle where the control rod from the HCV attaches. Put a little grease on the nub of that connection. Now slide the control arm off. With the key on, engine off, push the control rod up. Air should flow into the air bag from the air supply. Pull the control arm down, air should escape from the HCV. This test will tell you if the travel system is functioning properly.

If the problem is that the HWH system will not go into Level Mode when you push the level button, then there is a very good trouble shooting sequence to perform. Look for trouble shooting manual for 600 or 680 series air leveling on the HWH site. I would just link it here, but I am not smart enough to use this iPad.

I am assuming the E brake is set. It wouldn’t hurt to pop it in and out a time or two. If the HWH isn’t getting a signal that the E brake is on, it will NOT go into Level mode.