Hydraulic jack retraction sequence after pressing Hitch Height?

[ajg617]

Can anyone confirm what the retraction sequence should be after pressing Hitch Height? Worked as I expected for first four-five months - press hitch height, 4 rears retract, then front legs extend. The rears stopped retracting for the next six months and had to press retract all repeatedly to get them to go up. Started retracting again in April after winter maintenance with an Amp pull of up to 126Amps.

According to LCI tech, the whole issue resulted from removing the batteries after which 'they say' you must reset zero point calibration once reconnected or the 'brain' will get confused. First I had heard of that, but sure enough the day before I dropped it off, I reset zero point. Now the four rear jacks will not retract after pressing Hitch Height (though I no longer have the high Amp draw on retract all). Nobody at GD or LCI customer service seems to know if they should or should not. Not the only 'brain' that is confused now. Sometimes yes, sometimes no makes me think there is a fundamental problem that the dealership and I have not been able to figure out.

[Country Campers]

It should operate as you described, four rear retract then front to hitch height.
Have you turned any of the valves?
How is the oil level?

Brian

[ajg617]

It should operate as you described, four rear retract then front to hitch height.
Have you turned any of the valves?
How is the oil level?

Brian

Oil's topped off and clean. Have never touched the valves. The rears wouldn't retract from Oct-Apr after pressing Hitch Height. Then started retracting in April (when picked up from dealer for warranty service - nothing hydraulic) - first time since last Sep. Since last Thursday, won't retract after pressing Hitch Height - forced up when front legs extend.

[TedS]

I didn't think the rear jacks could be pushed up. I thought they had to be powered up. Maybe that's a clue.

[ajg617]

I didn't think the rear jacks could be pushed up. I thought they had to be powered up. Maybe that's a clue.

Not so sure with the hydraulic jacks - seems like the fluid just gets pushed back into the reservoir.

[Country Campers]

The rear jacks are power down and power up, same as the front. The middle will only move when the rear is either down to a certain pressure or all the way up.

Brian

[ajg617]

The rear jacks are power down and power up, same as the front. The middle will only move when the rear is either down to a certain pressure or all the way up.

Brian

But all six are driven off of the one hydraulic motor up front? If what you say is true, then there has to be a fault somewhere? I've seen what you are saying - it worked exactly that way when we first took delivery and again between April maintenance and June - the 4 rears always went up - mids first than two rears. That's when I was pulling 126Amps which caused me concern. They are no longer retracting but getting 'pushed' up as the front legs extend. Maybe the LCI tech was correct in pointing to a 'brain' problem.

[Country Campers]

There are special sized orifices in the lines that "force" the jacks to do certain things at certain times.
Notice when you drop the front gear, door side drops first until contact is made then the other side catches up.

One of your orifices could be clogged or partially clogged, reason for asking about fluid earlier.

Brian

[TedS]

There may be a loose wire to the mid and rear jack retract solenoid valve, but the extend valve may be OK allowing oil to return to tank.

The front legs are plumbed in parallel and the leg with the least resistance moves first. When it grounds, the other leg will extend(less resistance than the leg that's grounded). Then they move in parallel to lift the trailer.

[TedS]

Here's one version.

[ajg617]

All 4 rear go up, but not with a single button press (i.e. hitch height or retract all) consistently and this has changed multiple times since we took delivery. I've always been able to fully retract them, but not with the same sequence of button presses - sometimes hitch height raises them, sometimes not but retract all will.

[TedS]

It then sounds like the circuits and hydraulics work. That would lead to suspecting the control board is not reliably sequencing those circuits. Replace the control board.? I don't know how to troubleshoot the board components.

[ajg617]

It then sounds like the circuits and hydraulics work. That would lead to suspecting the control board is not reliably sequencing those circuits. Replace the control board.? I don't know how to troubleshoot the board components.

It's in the shop now. Dealership says it tests fine. LCI tech says the control board is likely the problem. GD tech says motor. I tend to agree that the control board logic is getting messed up. What makes it more interesting is this 310 has the "Level-up Advantage" controller which is no longer available from Grand Design. Looked like a short production run and the replacement PN is not in the parts lookup site.

[TedS]

I saw some available on the LCI site and eTrailer site.

[Country Campers]

You may want to gently "push" for an updated controller, maybe it would be a direct replacement.

Brian