Mystery Gray Wire in Level-Up Harness: Factory Splice or Wiring Error?

[CraigBinFL]

Last fall, while helping me work through some problems with my Level-Up system, LCI diagnosed the problem as being with my wiring harness, so I bought a new one. I am finally getting around to installing it and ran into a problem matching up the connections. I took "BEFORE" pictures, so I knew (most) connections and I disconnected and connected the wires one at a time, so everything was matching. ALL the wires to the solenoids and pressure switch are correct. Unfortunately, when I got to the bundle that connected to the Dual Polarity Solenoid and power from the 50A breaker, I ended up with one wire from the old harness that wasn't connected to anything.

I called Lippert and they tried to help, and ending up sending me a link for the Level-Up® LCD 5th Wheel OEM Installation Manual.
Page 19 has a wiring diagram, but as typical, it does NOT match my trailer. Possibly because it doesn't account for wiring for the slide-out solenoids??

Where the manual specifies a red wire, with a 10A fuse block, connecting to the 50A breaker, my trailer has a gray wire attaching to the (black) wire from the breaker. Those are both connected to a red wire with a 10A fuse block, that goes to parts unknown under the trailer. The harness has an orange wire that is not in the manual. It connects to a yellow wire that also disappears under the trailer.

When I went to connect the red wire with the 10A fuse block, I discovered that wire in the old harness was not connected to anything!! Going back through pics I took last fall, I can see that wire has a bare end, not connected to anything.

Can anyone tell me what if anything that wire should be connected to?

I realize not all installations are the same, so YMMV. FYI I have a 2015 Montana 3582RL. My Level-Up in the maintenance bay, mounted vertically above my batteries. The solenoid bank has connections for Curbside, Roadside and Slide-Out. The Landing Gear solenoid is directly on the landing gear, so there is a separate wiring bundle that goes out there.

Thanks in advance!

 

[ChuckS]

The wire harness you ordered and are replacing IS ONLY for the leveling system... The hyd slides also require connections and are not in that harness...

On the extend manifold that third Hydac valve controls the hydraulic slides anf there are two extra wires connected on the dual polarity solenoid... these are the send wires from the slide out switch in your RV to send 12 vdc signal to solenoid to run motor CW or CCW

Color coding on that year Montana was not yet standardized so the colors of the wires from the solenoid on the pump motor to the slide switch could be anything... Also the wire color used to the Hydac valve solenoid for the slides could be any color...

Images from my unit showing inside slide out switch wiring and wires on the solenoid on the motor from the switch

Edited to add Lippert slide switch wiring for hyd slides … color code Lippert used does not match what Keystone used on my inside slide switch but it gives you the connections

I forgot to mark the BLUE wire on the inside slide switch but that is the 12 vdc power wire that runs to the extend manifold hydac valve solenoid for the slides... It sends 12 vdc when extend or retract signal is sent to the motor solenoid to energize the the slide valve coil

 

[CraigBinFL]

The wire harness you ordered and are replacing IS ONLY for the leveling system... The hyd slides also require connections and are not in that harness...

On the extend manifold that third Hydac valve controls the hydraulic slides anf there are two extra wires connected on the dual polarity solenoid... these are the send wires from the slide out switch in your RV to send 12 vdc signal to solenoid to run motor CW or CCW

Color coding on that year Montana was not yet standardized so the colors of the wires from the solenoid on the pump motor to the slide switch could be anything... Also the wire color used to the Hydac valve solenoid for the slides could be any color...

Images from my unit showing inside slide out switch wiring and wires on the solenoid on the motor from the switch

Edited to add Lippert slide switch wiring for hyd slides … color code Lippert used does not match what Keystone used on my inside slide switch but it gives you the connections

I forgot to mark the BLUE wire on the inside slide switch but that is the 12 vdc power wire that runs to the extend manifold hydac valve solenoid for the slides... It sends 12 vdc when extend or retract signal is sent to the motor solenoid to energize the the slide valve coil

Thanks, but the harness I'm installing is an exact replacement for the old one and does include wiring for the slide solenoid.

All I need to know is whether the red wire with 10A fuse block is supposed to be connected to something or capped off. In replacing the harness, one lead at a time, I discovered that wire on the old harness wasn't connected to anything, but had a bare wire exposed end. Not good, for what I would expect to be a hot wire.

 

[CraigBinFL]

Tracing the gray wire from the landing gear through the bundle to the nine-pin block I found that another gray wire is spliced into it. that wire in my old harness was connected to the positive wire coming from the 50A breaker. No wonder my landing gear always showed 12-13 volts!! I now wonder if it was wired correctly from the factory?

If someone could check their comparable system: follow the landing gear hot wire from the solenoid into the harness. Is there THIRD end for that color wire? To what does it attach? Is it paired with the hot wire coming from your slide solenoid?

 

[ChuckS]

On the solenoid for the pump motor extend/retract connections are two wires for the leveling system...

There also has to be two additional wires on the extend/retract connections for the slide switch to be able to send 12 vdc to the solenoid as well as the Hydac valve coil 12 vdc power wire...

The HOT wire on the solenoid should be coming from a resettable 12 vdc breaker to power the solenoid and motor...

The single red wire with fuse holder applies 12 vdc to front forward controller ALL the time... even when leveling and slide system is not in use...

The Gray wire is 12 vdc wire to Frt LG hydac coil from the front forward controller and nothing else should have ever been spliced into it.. Gray wire should be solid wire from the plug at the coil to the molex connector at the front forward control

If there is constant 12 vdc on that gray wire then someone has rewired something along the way.... or you have a problem with the front fwd controller

** The slide switch would also have constant 12 vdc to it ( its a momentary on ) switch.... Id be looking at how the slide switch is getting 12 vdc

Edited to add info about front forward controller, gray wire should only have 12 vdc when the Frt LG is selected to operate or auto level in use..

 

[CraigBinFL]

On the solenoid for the pump motor extend/retract connections are two wires for the leveling system...

There also has to be two additional wires on the extend/retract connections for the slide switch to be able to send 12 vdc to the solenoid as well as the Hydac valve coil 12 vdc power wire...

The HOT wire on the solenoid should be coming from a resettable 12 vdc breaker to power the solenoid and motor...

The single red wire with fuse holder applies 12 vdc to front forward controller ALL the time... even when leveling and slide system is not in use...

The Gray wire is 12 vdc wire to Frt LG hydac coil from the front forward controller and nothing else should have ever been spliced into it.. Gray wire should be solid wire from the plug at the coil to the molex connector at the front forward control

If there is constant 12 vdc on that gray wire then someone has rewired something along the way.... or you have a problem with the front fwd controller

** The slide switch would also have constant 12 vdc to it ( its a momentary on ) switch.... Id be looking at how the slide switch is getting 12 vdc

Edited to add info about front forward controller, gray wire should only have 12 vdc when the Frt LG is selected to operate or auto level in use..

I agree with all your logic on this.

The trouble is that both the old and new harnesses have a gray wire spliced into the gray wire from the controller to the landing gear. Thus, it is a factory decision not some after-the-fact rewiring. What else would require power when operating the landing gear?

The 5er is in storage so I would need to check about slide wires to the dual polarity solenoid, but if there, they are not part of this harness.

I know there is a wire from one of the breakers that provided power directly to the slides, so it is not part of that harness' design either.

 

[ChuckS]

The slide switch HAS TO send 12 vdc to the extend and retract sides of the solenoid as well as the Hydac valve coil otherwise the motor would not run and the coil would not eneregize to open the Hydac valve and allow fluid to flow to move the slides...

The Gray wire Sends 12 vdc power to the Frt LG Hydac coil only so there is no reason for another wire to be spliced... My harness is not like that... Lippert 6 point Hyd system, three slides controlled via single wall switch..

Wire pinout from front fwd controller ( NINE pin molex plug ) showing gray wire runs directly to Frt LG Hydac coil with no splices...

Single red wire plugs into other molex plug and is the ONLY wire on that plug.. It has a RED covered ATC style fuse in line near the source of its power and then feeds 12 vdc directly to the Fwd control box..

Are you the original owner of this unit? I cannot fathom why a harness comes with a splice in the gray 12 vdc power feed to the Frt LG coil...

Edited to add.. the ONLY time the GRAY wire should have 12 vdc to it is when you are operating the level up control panel to run the Frt LG jacks... when the Frt LG is not being operated that GRAY wire should have 0 vdc reading on it....

Other wise the Frt LG would have an OPEN Hydac valve ALL the time allowing fluid to flow through and move those LG jacks

Then again... maybe my logic is out in the pasture with the rest of the old cows!!

 

[ChuckS]

Lippert Video removing and installing harness.... They do not show the slide Hydac coil wire since they are only dealing with the level up wire harness..

 

[ChuckS]

I noticed your wiring harness is

L50-258540 Rev E Harness​

Not sure what the Rev E means..

This is the standard 9 pin wire harness from Lippert for a six point hyd level up system

Level Up® 9-Position RV Harness | Lippert

Level your RV faster with a Level Up® 9-Position Harness from Lippert, leading manufacturer of leveling parts and accessories in RV industry.

www.lippert.com

 

[CraigBinFL]

The slide switch HAS TO send 12 vdc to the extend and retract sides of the solenoid as well as the Hydac valve coil otherwise the motor would not run and the coil would not eneregize to open the Hydac valve and allow fluid to flow to move the slides...

Agree. 5er is in storage so I need to check the Dual Polarity solenoid for slide related wwires. One end of the orange wire in the harness connects to the solenoid at the slide hydac valve. (Maybe I'm adding confusion by referring to the connections at the hydac valve coils as solenoids?)

The Gray wire Sends 12 vdc power to the Frt LG Hydac coil only so there is no reason for another wire to be spliced... My harness is not like that... Lippert 6 point Hyd system, three slides controlled via single wall switch..

Agree. But my gray wire does have a factory splice & nobody seems to know what it is for. Love Lippert & Keystone for their lack of standardization & documentation!! You'd think that if I gave them their part number, they could tell me what everything is supposed to connect to. I have same Lippert 6 point hydraulic Level-up system with two hydraulic slides on a single wall switch.

Wire pinout from front fwd controller ( six pin molex plug ) showing gray wire runs directly to Frt LG Hydac coil with no splices...

My front forward controller has a 9-pin molex. It's configuration matches the drawing supplied by Lippert.

Single red wire plugs into other molex plug and is the ONLY wire on that plug.. It has a RED covered ATC style fuse in line near the source of its power and then feeds 12 vdc directly to the Fwd control box..

Mine has that BUT the wire is factory spliced with that splice going to the 9-pin molex. The other end with the fuse block was not connected to anything and appears to have never been used.

Are you the original owner of this unit? I cannot fathom why a harness comes with a splice in the gray 12 vdc power feed to the Frt LG coil...

No. 2nd owner but the old harness had no signs of being modified and the new harness directly from LCI, with matching part number is identical. I can't fathom it either. Nor why they used the gray wire to provide power to the controller as well as the landing gear.

Maybe I should just make connections as all sources indicate they should be and just see what no longer works with that gray splice not connected to anything?

 

[ChuckS]

Agree. 5er is in storage so I need to check the Dual Polarity solenoid for slide related wwires. One end of the orange wire in the harness connects to the solenoid at the slide hydac valve. (Maybe I'm adding confusion by referring to the connections at the hydac valve coils as solenoids?)

Agree. But my gray wire does have a factory splice & nobody seems to know what it is for. Love Lippert & Keystone for their lack of standardization & documentation!! You'd think that if I gave them their part number, they could tell me what everything is supposed to connect to. I have same Lippert 6 point hydraulic Level-up system with two hydraulic slides on a single wall switch.

My front forward controller has a 9-pin molex. It's configuration matches the drawing supplied by Lippert.

Mine has that BUT the wire is factory spliced with that splice going to the 9-pin molex. The other end with the fuse block was not connected to anything and appears to have never been used.

No. 2nd owner but the old harness had no signs of being modified and the new harness directly from LCI, with matching part number is identical. I can't fathom it either. Nor why they used the gray wire to provide power to the controller as well as the landing gear.

Maybe I should just make connections as all sources indicate they should be and just see what no longer works with that gray splice not connected to anything?

That GRAY wire should NEVER supply 12 vdc to the front fwd control module.. It SENDS 12 VDC power to the Frt LG Hydac valve solenoid ONLY when the Frt LG is being acuated from the level up panel in manual more or during auto level....

I wish I could offer more precise info.. Let the group know how it all turns out. I've exhausted my feeble understanding of the system and how it should be wired

 

[CraigBinFL]

@ChuckS thanks for your insights. I decided to connect the red, fused wire where the gray splice was and leave the gray splice unconnected to anything. Landing gear, levelers and slides all work as they should. Maybe some day we'll figure out what that splice was for.

BTW, I pulled the cover off the command center and checked the wires on the slide switch. One pair matches those on the dual polarity solenoid.

 

[ChuckS]

@ChuckS thanks for your insights. I decided to connect the red, fused wire where the gray splice was and leave the gray splice unconnected to anything. Landing gear, levelers and slides all work as they should. Maybe some day we'll figure out what that splice was for.

BTW, I pulled the cover off the command center and checked the wires on the slide switch. One pair matches those on the dual polarity solenoid.

Glad it all worked out good for you.... Yup.. that slide switch has to send 12 vdc to extend and retract connections on solenoid or slides would never move.... Have no idea what that splice is for on the REV E cable.

I went out and checked my wiring again and the gray wire has no splice wire and matches the harness I previously posted a Lippert parts link about...

Maybe someone else can shed some light as to why the gray wire has a splice and non connected end on. it... You can always verify that gray wire ( unused ) has no 12 vdc power on it by simply measuring with your multimeter... It should only show 12 vdc when you actuate the Frt LG ...

Why there would be a outgoing splice on that wire is beyond me BUT maybe that unused gray wire was intended to be used also on a Class A or C rig and would be used to power up a Dash indicator light when Frt LG was actuated as it would send 12 vdc from fwd control box connection on that gray wire when Frt LG was being activated

 

[ChuckS]

I should have asked this before but.... what exactly were the issues you originally were having with the level up system prior to Lippert telling you to replace the entire wire harness?

 

[CraigBinFL]

Landing gear extended/retracted whenever levelers or slides were extended/retracted.

I replaced the hydac valve and the LG passed the bypass test. When I noticed the LG coil was warm despite not being used for hours, LCI recommended a voltage test with and without the 9-pin plugged into the controller. Finding 12+v present both times, LCI concluded there was a break somewhere in the harness allowing power from red wire to cross over to the gray wire for the LG & had me buy a new harness. It was when I went to install it that I discovered the factory splice in the grey wire was connected to a hot wire from the breaker.

 

[ChuckS]

Yup that explains your original issue. With 12 VDC on that spliced gray wire the frt LG Hydac coil was energized all the time pulling open the normally closed Hydac valve.. thus letting fluid flow anytime anything else hydrauilc was operated

I was curious and have looked around quite a bit and cannot find any referencE as to what the purpose of that spliced gray wire was ever intended for..

It would be interesting to hear from any other Montana owners to have a look see at their factory OEM wire harness on that gray wire..

I traced mine on my Alpine and it’s a single gray wire from that 9 pin molex plug to the Frt LG Hydac coil

 

[CraigBinFL]

Trouble is that harness has been that way since I got the 5er in 2021. Problem only showed up last fall, when the circuit breaker burnt out. Even then, that part of the wiring was never touched.

The problem coincided with replacing a hose from the manifold to the curbside leveler and then substantial debris in the reservoir. First suspicion (& most likely from troubleshooting guides) is debris in valve, but disconnecting power to the LG eliminated the problem, so it seems conclusive it was that gray wire. Cascade of problems makes me wonder what I may have done in replacing the circuit breaker that may have lead to this.