"Jacks Down" warning came on while driving

[gator67]

We were driving down the interstate when all of a sudden I heard an ominous beeping sound. I looked at all the dials and lights, my GPS, my tire sensor monitor, and all looked okay. I finally saw in the odometer display that it said "Jacks Down". I immediately pulled over, stopped and turned on the HWH console. The red light for the left rear jack was on. I pressed "store" and the light went out in about one second. I went to check the jack and it was up. I should have checked it before I hit the "store" button, but in my panic, it didn't occur to me. Has anyone else experienced this? Could my jack have drifted down just a bit? If so, why? Is this a symptom of something else?

[Doug & Debbie]

This has happened to us several times. The first time we stopped as you did to retract but after discussions with other Alpine owners we now just do it while we are driving down the road. As one owner said, "that is what the co-pilot is for". From what I have heard there is no fix for this except to turn on the HWH and hit the store button. Doug

[Rich and Cork]

Quote:

Originally Posted by Doug & Debbie This has happened to us several times. The first time we stopped as you did to retract but after discussions with other Alpine owners we now just do it while we are driving down the road. As one owner said, "that is what the co-pilot is for". From what I have heard there is no fix for this except to turn on the HWH and hit the store button. Doug

Yah, you can't even turn up the radio loud enough to drown out the sound.

[Ken Roberts]

Jerry, the easiest fix in the world is to travel with the store button on. It will not hurt anything and may save you a change of underwear when you are cruising along an interstate. BTW, this tip came from an HWH tech while we were in Moscow, Iowa for a jack repair. That was 3 yeares ago and the only problem we have had with the Jacks Down alarm is when yours truly forgets to hit the store button, generally after a rest area or a fuel stop. Be safe out there, Ken...

[RVThere]

That used to happen on my old Itasca Suncruiser and I would always retract 'on the fly'. It would take a while for that jack to get low enough to hit the road so you have plenty of time to hit the store button. It's not a panic situation.

[bcbowers]

I believe the ACA web site has an archive record of a "Gear Head" session (Technical Section) in which several manufacturers particpated for Q & A including HWH. You might want to read some of the Q & A pertaining to the hydraulic jacks. It appears that the left (driver's side) rear jack is notorious for causing a "Jack Down" alarm. It's happened to use several times.

Basically, a representative from HWH had stated that you should leave the hydraulic system on for several minutes (5 - 6?) "AFTER" the "Travel" light comes on. Apparently, there is an hydraulic equalizer in the battery compartment (long cylinder object) mounted up high and to the right when facing the compartment (my rig). The extra time allows for adequate equalization otherwise the left rear jack has a tendency to drop slightly at some "inconvenient" time - like driving down the road.

Hopefully, I'm repeating what I read correctly!? Otherwise, one or more of the more experienced owners will probably correct what I've said. The "Gear Head" session is VERY interesting and should be considered MUST reading if you haven't read it.

[wa8yxm]

What make and type of jacks.. If answer is NOT power gear hydraulic stop reading NOW.

If it is Power Gear Hydraulic the "JACKS DOWN" sensor is a float valve in the fluid reservoir.

With the jacks FULL UP, add a bit of the proper fluid (NOTE: may not be what you think it is) as directed in the owner's manual

[Old Scout]

Nope--its HWH and the driver-side rear jack is "famous" for leaking down. Lots of different remedies on the forum to help prevent it but nothing will cure it--ie., new springs, wipe down jack with fluid, and letting the control panel cycle to off [after pushing "Store"] before starting engine. No equalizers involved, simply stated its the longest hose run so the fluid can expand and sometimes its heat from the engine compartment.

[Jim A]

Right or wrong, when I am preparing to leave, I turn the key to accessory and store the jacks. (I don't want to listen to the buzzer while waiting for the jacks to retract when the engine is running.) As soon as the green light comes on, I turn the key to start the engine. I have never waited past that unless I had something else to do while the jacks were retracting. Only once in 6+ years have I had a jack down warning come on while on the road, that on a very rough section of I-5 in the Tejon pass on a hot day.

I have never lubed the jacks, changed springs, or anything to help them. I guess I am just lucky. The driver side rear jack is always the last to fully retract. But once retracted to the point of turning off the red LED and turning on the green one, it has always stayed. I was never aware that the jack store sequence would time out!

So it is possible for them to work as designed. Unlikely apparently, but possible.

[takepride]

I have always done as Jim A, but have had the alarm problem occasionally. I will try Bob's method next week. I'll retract slides, then jacks, then start, then re-hit the store button. We'll see what happens. It seems to make sense and is the first time I've heard about the hydraulic equalizer, though I think I've seen it.

[EngineerMike]

The equalizer cylinder in the battery compartment is for the DS closet slide. No relation to jacks. You'll see another equalizer (larger as would be appropriate) in the PS basement for the DS "main" slide.

Jacks are a one-way operation from the pump/manifold. I.e. pump runs to create pressure & solenoid valve in the manifold opens needle valves to allow pressure to flow to the jack rams (2 at a time to avoid bending the frame). The Retract cycle opens the jack solenoid valves without running pump, and first coach weight then spring power retracts the jacks, pushing fluid back to the reservoir.

[takepride]

eMike:

That would mean the only reason the jack creeps down is (heat) expansion of the fluid remaining in the line after the needle valves. Being that the DS rear is furthest from the pump, it would have the most fluid to expand. Maybe a refrigerated cooling line wrapped around the hydraulic line would help.... Hmm.....

[EngineerMike]

I'm thinking a worn needle valve (these can be adjusted BTW) would allow leakage, maybe a coupla other reasons also.

The needle is operated by the solenoid, and the nose piece on the end of the valve assembly is adjustable using a slim nut that holds the nose piece to the solenoid body. You turn the nose piece in to get a tighter seat. Nose piece is aluminum and needle is steel so the hole in the nose piece where the needle seats could get sloppy and maybe a partial turn on the nose would seal it up?
Worth a try if you have a problem recurring. I have specially machined plugs to seal the manifold while doing surgery of this type if you are interested.

[Old Scout]

Not sure I would go with the "surgery" option on the needle valve assembly. Assuming the solenoid is closed in the neutral state, the needle is held open by the store command then closes once the command panel cycles to off [if not a closed neutral, solenoid would have to be energized to hold the jack down--I think].
A bit of leak-by in the closed/neutral position would actually help to release some of the expanding fluid in the jack assembly/hose. Cleaning the jack rams, good retract springs, letting the store command completely cycle, or just being lucky, seem to be the only options for the DS rear jack. Equalizer tubes and refrig lines [smile] notwithstanding, you should probably avoid lowering the jacks at rest-stops or during other short stops where residual engine heat is going to make the fluid expansion problem worse.