HWH series 2000 - no air to pass side rear bags

[Mike Shumack]

Getting ready for a trip.
Aired up coach, put in Travel mode and the drivers side (rear) lifts real high but passenger side does not lift at all. I'm not getting any air to the rear pass side air bags.
Has anyone else had a problem where passenger side rear airbags would not fill?

Looking at service manual - I ran through several of the tests/checks:
Tests From the HWH control panel:

Dump All - works all air exhausts.
Raise All -- does not fill passenger side rear bags
Raise one side at a time - will not raise passenger side.
Travel mode - will not raise passenger side (drivers side raises).

All of the LED lights in the HWH box appear to be normal (lit when should be, off when should be off). Travel mode is going green. But pass side is not raising.

I'm working through the steps in the troubleshooting manual, and I noticed a comment about the HWH Warning light - Says it HWH warning light should be on anytime the ignition switch is On. Mine does not come on (I checked the bulb first).

So. per the instructions in 2d (attached) I checked power on wire 6121 and I have no power. Troubleshooting manual says Control Box is bad.

Did I miss anything (that box is not cheap).

Has anyone else had to replace their HWH control box - is so, what where the symptoms?

Also, the manual says:
"If the Control Box is removed, +12V ignition power must be applied to the travel solenoid wires (GRAY) 1700 in the front and (GRAY) 3700 in the rear air harness. This will allow the height control valve to function."
So this should act as a "bypass" for the Travel Solenoids - and if passenger bags then raise to normal height, that would further confirm the Control Box is bad. I'm just not sure I can get to the rear HWH valve body (maybe these wires are also located in the front electrical bay at Control Box).

UPDATE -- I ran 12V power to Travel solenoids via wires 1700 and 3700 (at the HWH box electrical plugs) and the passenger side rear airbags still do not fill. The manual did not mention needing to provide a ground for the Travel solenoids (maybe I need to).

I have a call into to Paul Maddox (HWH) now.

[Steve Huber Co-Admin]

Mike,
There are right and left side air bag inflation valves. Make sure the right side one is adjusted properly and that the clamp hasn't come loose. This would keep the bag from inflating. They are normally located just forward of the rear axle.
Steve

[Mike Shumack]

Steve, the ride height valves look okay. I didn't pull the air lines off but mechanically it looks okay. Both sides look to be connected the same.

But even if the RHV was bad, I think the Leveling system would still raise the passenger side (in auto mode or in manual mode) - from the manual it looks to be a separate air supply that does not go through the RHV circuit.

This problem has me confused. The Pass side airbags will not fill in Travel mode or Leveling mode.

Thanks for your ideas on this.

[Mike Shumack]

So at this point I ran two new 1/4" lines from the air rear passenger air bags to the ride height control valve. This puts air in the passenger bags and I drive the coach now.

The drivers side rear air bags (and Tag axle bags) are still going through the HWH valve bank, so I still need to put HWH in Travel mode to air up drivers side.

I'm not sure of the consequences of this "temp repair". I think it will be fine to take coach on the road this way.

I left the old airbag lines coming out of HWH valve bank disconnected and not plugged. So if the Travel solenoid was to start working again air would just blow out the lines (like a blown hose). But it is unlikely the problem is going to fix it self. Maybe I should plug those lines to be sure.

[Mike Shumack]

I spoke with Paul Maddox (HWH) today. He was nice enough to call me on a Sunday. We went through everything and decided the Control Box is bad.

It looks like an internal relay went bad which is preventing all functions for the passenger side rear bags from working.
I'll be sending it in to HWH for repair.

[David T. Richelderfer]

Perhaps we can get a 2-fer...  2 repairs for the cost of 1?  Sorry to hear you are having HWH control box issues too.

[Mike Shumack]

Once I pull the Control Box and send it in for repair, I think that would be a good time to rebuild the HWH 6-packs on the rear. It's real hard to get to (need to drop drive shaft I think) but this would be the time to do it.

BTW - all that frame twisting cracked my windshield, so I have to get that replaced too.

Would it be smart to get a new "rubber gasket" for the windshield - if one is even available (so glass installer does not need to reuse the old gasket)?

[Steve Huber Co-Admin]

Mike,
If it is hardening I'd consider it. Won't get any better with time.
Steve