Skip to main content ↑ ↓
Topic: HWH communication cables mystery (Read 484 times) previous topic - next topic

HWH communication cables mystery

So, I'm curious if it's typical or unique to my coach, but there are two apparently exactly the same type communication cables from the backside of the HWH control pad at lower left of Driver's dash and both lead to and terminate in the HWH (metal) box enclosing circuit boards and the fuses.  Best I can guess is either Foretravel, in a bit of "infinite wisdom" and great planning installed the two, which outwardly appear to be exact duplicates, as a helpful bit of redundancy in case one failed (so you could just swap the one connected with the other, unconnected one and be good to go), or probably more likely, one was added as a repair because the original one had indeed failed...but then why leave the failed one there, why not cut it or remove it?  Mind, only one was connected and it appears only one can be connected since there is only one female connector at each end, i.e. dash and box in bay.

It gets more interesting.  When the coach was inspected by a hired mechanic pre-purchase it was noted the HWH leveling system appeared to not be working, but it was drivable as it did rise to and maintain ride height easily, in spite of at that time having a significant leak in two airbags. (The coach was in KY and I in DE at the time).  This was Aug 2021.  Went ahead with the purchase as everything met my expectations for the price.  Had new tires and all 8 airbags replaced before it was delivered by hired driver.  (I had planned to pick it up and drive home, but found out after purchase and thankfully before I flew out there, that at the time I was not in fact licensed to legally drive a vehicle over 26,001 lbs GVWR without a non commercial class B addition to my license, which I could not get without providing my own vehicle for the driving portion of the test for said licensing addition.  Catch -22, courtesy of the state.). Anyway, hired driver said the coach drove great and gave him no issues.  Easier than other coaches he delivered.  Yes, I said, it's a Foretravel; I would hope so.

Since delivery, I've driven it back and forth to the DMV, taken friends out to show the coach, and moved it repeatedly.  Always without fail it went to travel height quickly and the air pressure gauge would show it cutting in around 90/100psi and cutting out At 125PSI, rarely 130. But never any lights, travel mode or otherwise at the HWH pad.

I'd moved it to a monthly space at a campground where I could finally get to do the planned upgrades and a few needed repairs. I booked 2 months. 2 grueling months later and time to move out today.  One of my repairs was to look into why the HWH leveling was not functional.  I found the box, checked all the fuses.  Opened the dash, checked voltage to the pad.  All good.  But hey, here's this extra(?) communication cable.  Each had a different, identifiable mark on each end.  I guessed the ones currently connected could be the reason I had no lights or functions of any kind at the pad so I swapped it for the other unused cable.  Didn't test it as it was day before yesterday and I knew I'd be starting up today and didn't want to idle the engine needlessly.  This morning I start it up to move out.  Engine starts, air gauge moves to 100PSI. Parking brake still on, I go out to pull the chocks.
What's this?!?  The coach is still down on the tires.  Yikes.  Not good.  So I turn off the engine and ponder.  I figure the only thing that's changed was my swapping the communication cables.  I swap them back to how they were.  Start up.  Coach airs up to 100PSI and rising. Go outside to check and sure enough, it's at proper ride height on all tires.  So off we go, eventually and uneventfully to the storage yard 40 miles up the road.

So, every time it's been driven (since my purchase anyway) it's done so at ride height, without any indication of travel mode on the HWH panel. In fact, the panel seems DOA and I'm clearly going to have to call HWH at some point about a pad replacement or rebuild.  But am I missing something with these two communication cables.  I can't imagine there are supposed to be two of them and especially when  one of them actually keeps the coach from rising at all.  Also mysterious the air gauge would still show what would appear to be adequate pressure to raise the coach, even though it didn't (with that bad cable anyway).

Thanks for hanging thru the lengthy description of the problem and I appreciate any thoughts.

Bill
95 36' U295  CAI, build #4757
—>formerly homed in the midwest, now mobile again,
      mid-atlantic for the present.

Re: HWH communication cables mystery

Reply #1 –
It's past my bedtime, so just a few quick comments.

I have no explanation for the two communication cables.  I doubt they were both installed at the factory, but who knows?

The air pressure system is completely separate from the HWH leveling system.  Of course, you need sufficient air pressure to allow operation of the HWH system, but they are not connected in any electrical circuit.

The only part of the HWH system needed to achieve proper travel height is the TRAVEL solenoids in the front and rear 6-pack manifolds.  There are two travel solenoids in each 6-pack manifold - one for each side.  The travel solenoids must be energized to allow air pressure to reach the height control valves (one in front and two in the rear).  The power to energize the solenoids originates in the HWH control box.  The fact that your coach goes to travel height would indicate that the (metal) control box is getting power.  "Open Travel Solenoids" is the default command built into the HWH control box when the leveling system is turned off.  See paragraph below from the 600 Series Service Manual:

7. TRAVEL MODE: With the ignition on and leveling system off, the coach should return to the proper travel height. The travel solenoids are energized allowing the height control valves to function.
NOTE: If the ignition is on and the park brake is released the leveling system should turn off and the coach should return to ride height.

I would say get the control pad working, whatever that takes, then see how it goes.  Your whole problem might just be a dead control pad.

If you have the HWH 600 Series leveling system on your coach, you should have a copy of the service manual.  If you don't have a copy, follow this link:  https://www.hwhcorp.com/ml11148.pdf

The service manual includes a useful trouble shooting section.  For a completely dead control pad, the manual says:

Part 2
With the ignition switch on:
a. (Neither) The green "TRAVEL" light nor the master warning light is lit.

Whenever the ignition switch is "ON" one of these lights will be lit but never both at the same time. If neither light is on, check the power to the control box. The yellow wire in the power harness will have +12 volts with the ignition in the "ON" position. The red wire should have +12 volts with the ignition in any position. If the yellow wire has power replace the control box. If not, trace the yellow wire to its source.

1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: HWH communication cables mystery

Reply #2 –
Make sure that the salesman switch by the door is turned on as that is what supplies voltage on the yellow wire.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: HWH communication cables mystery

Reply #3 –
I am familiar with the salesman switch.  I use it a lot.  When I'm in the coach it's on.  It's a reflexive action. 

I do have the HWH operating manual and service manual.  Not finding it all that helpful especially as it doesn't explain if there are normally two of these duplicated cables or if this is an anomaly with this coach. I suspect the latter.

I'm pretty sure there is not a problem energizing the travel solenoids since I can, with at least one of these duplicate cables connected, raise the coach to travel height and maintain it. The coach has travelled a total of 1200 miles that I know of and likely more under the PO in this fashion, not once with a single light lit on the control pad and no indication of travel height other than air pressure at the dash gauge. 

So there are essentially several separate issues: 1) no functions available at the control pad and no lights, including no indication of travel mode  2) coach does raise to travel height and maintain it with one comm cable connected, but NOT with the other duplicate one swapped in  3) there are two comm cables, for a total of 4 female connectors  if I remember correctly, yet only one male connector at each end i.e. one at the dash control pad and one at the control box in the bay, for a total of only two male connectors.

perhaps a pic would help....took me a bit to get one to upload, but here it is.  In the pic of the control box, you can see a number of the usual (white) wiring harnesses and only one (circled in red) black comm cable.  this is the one that is duplicated, though it's pulled aside in the photo so less visible but you can just make out the very end of it in the bottom left corner.  it's the only cable of any in the box or dash pad that is an exact duplicate and that is part of the mystery.

I guess for now the plan is to go ahead with a trip to FL, as there's not time to get a phone consult thru to HWH, ship them either the pad, box, or both and get it back before I'd need to head out.  I figure the coach travelled this way from KY and all around DE so I can't see why it shouldn't be able to go another 1100 miles ok this way.  Fortune favors the bold, no?    I can make the call to HWH from FL and proceed as they desire at that point.  On the odd chance someone recognizes what's up with these duplicate comm cables, I all ears. 

thanks,

Bill

95 36' U295  CAI, build #4757
—>formerly homed in the midwest, now mobile again,
      mid-atlantic for the present.

Re: HWH communication cables mystery

Reply #4 –
I would say that the original cable got damaged, so someone pulled a new cable in. They should have either removed the old one or at least cut off the ends. So as not to cause confusion.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: HWH communication cables mystery

Reply #5 –
Quote from: red tractor –
I would say that the original cable got damaged, so someone pulled a new cable in. They should have either removed the old one or at least cut off the ends. So as not to cause confusion.
 

Absolutely agree with that!  It's odd as the records are partially complete.  The owner immediately prior to me (I am the 3rd Earl of the estate 😉) kept decent enough records or at least receipts for the work done.  But I think the problem is due to the original owner, who did not seem to keep any records or those records somehow got separated from the coach.


I'd like to rebuild the six packs for front and back, but seems foolish to begin that until I can get the leveling system functioning.  Also I can't raise it high enough to get the safety stands I have (11") in place.

Bill
95 36' U295  CAI, build #4757
—>formerly homed in the midwest, now mobile again,
      mid-atlantic for the present.

Re: HWH communication cables mystery

Reply #6 –
You need to go through the HWH manual and do the troubleshooting exactly as it says. No shortcuts. Then you will know what the problem is.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins
 

Re: HWH communication cables mystery

Reply #7 –
Quote from: red tractor –
You need to go through the HWH manual and do the troubleshooting exactly as it says. No shortcuts. Then you will know what the problem is.


I appreciate the value of a manual, I really do.  In actuality I found and consulted the HWH manual before even approaching the forums.  I also used the forum search function and read copiously on a wide variety of postings and discussions on the HWH leveling system and problems and issues.  I learned a lot.  It was all a useful application of time but it did not adequately  illuminate the situation I described here, which I posted thinking it was possible someone had encountered something similar.  It's fair to say I think, at this point, that no one has, at least thus far, and that the whole duplicate cable issue is unique to this coach, either an oddity or more likely the result of some poorly executed prior attempt at repair by who knows who.  It's not the first fault I've found with the coach due to the previous owners, some repair service/facility or the factory and I'm also fairly sure it won't be the last.  For now, I'm willing to chalk it up to "C'est la vie" and not let the perfect be the enemy of the good as it does run well otherwise and doesn't seem averse to distances.

95 36' U295  CAI, build #4757
—>formerly homed in the midwest, now mobile again,
      mid-atlantic for the present.