More often than not I'll hit the extend rocker switch and the slide will extend about 2" or so and stop. I check the status lights in the bay under the slide and it shows "upper lock not unlocked". I'll turn the key off and wait a few minutes and upon retry, the slide will most often extend; ifnot I'll repeat and eventually cooperates. Retraction never presents any problem. Is there a solenoid or relay that may be intermittent? It's been behaving like this a few months and it eventually extends so I forget about it until the next trip where we repeat the exercise. Any troubleshooting tips. I tried calling HWH and they put me on their call back list....not like the old days where a tech would walk you through the recovery possibilities.
If it extends at all the the upper locking pins have most likely retracted, maybe not all the way. I am pretty sure there is a limit switch or something like that that senses that the pins have retracted. It may be misaligned or failing. If you can safely look at the top of your slide can you see any indiction that the pins are dragging along the top? If so that means they are not retracting all the way.
I recently wiped some plumber's silicone grease in the top and bottom outboard pin sockets. The slide would creak at the top sometimes when we were moving. That seems to have stopped.
I emailed you the 2001 680 series operator's manual, part list and HWH parts catalog.
Roger
Check the t switch on the blocks. It has a connection that might not be fully set. If you want to you can use a magnet to run up and down and it will turn the lights on the block too.