Community Forums

D. Moore · 08-03-2021, 01:59 PM

I have a 2018 Pace Arrow diesel on a freightliner chassis. Its has an intermittent problem that causes big headaches- intermittently.

This is the scenario: Occasionally running down the highway the air brake alarm will starting beeping, which is the alarm that is supposed to tell me that the unit has the air brake released but not in gear, or conversely that the unit is in gear but with the air brake engaged. I can relieve this alarm by sounding my air horn, thus releasing some air and the alarm goes away.

Also- and more of a headache- sometimes the Powertrain leveling jacks do not recognize that the air brake is engaged, so the control board will not energize. More often than not this also can be relieved by hitting the air horn. Which my camping neighbors appreciate. However on one occasion I could not get the powertrain levelers to recognize the air brake, thus the slides would not retract and the levelers were stuck down. Even putting the unit in drive gear did not retract the jacks. After a lot of plugging, unplugging, hot wiring slides, etc, the jacks retracted. But the mobile service tech and myself are not sure what we did to get this to happen.

So- frustrated and scared of getting stuck again- I sent it to the freightliner service center. After $900 and a lot of troubleshooting, they determined it was a fleetwood problem, everything on the freightliner side checked out, Just for my own satisfaction I personally replaced the air brake switch under the dash for $ 40 but it did not change anything. So then I sent it to an authorized fleetwood rv service center, who in turn can not find the problem but say it must be on the freightliner side.

That is my dilemma. Has any fleetwood owners or freightliner owners had as similar problem? Does anyone have any suggestions what to troubleshoot next?

Thanks!

Windward · 08-09-2021, 10:28 PM

Sounds like your stuck in a bad spot between the chassis mfg and the coach mfg and neither is much help. They are both pointing fingers at each other as they don't know what's going on, been there done that!

Traditionally, truck air alarms are for low air pressure in either the front or rear systems so you have some warning of loosing service brakes and to have time to get off the road before your spring brakes kick in. This is what Freightliner would be familiar with.

The coach mfg adds black boxes fed by sensors to interface with the myriad of devices, slides, levelers etc. to keep you from getting into trouble by moving when you shouldn't.

If I made an educated guess I'd bet you have; 1) a bad pressure sensor (there is more than one of these) feeding misinformation to a black box or 2) a bad black box. Both would be a coach issue not chassis issue.

I deliberately avoided a newer computerized coach for your circumstance. Not that older "simpler" coaches don't have their own issues, but at least it doesn't involve a hard to troubleshoot black box.

I wish you luck in finding out the problem.

KF5UMC · 08-10-2021, 03:18 AM

What does your 2 air tank gauges read in pressure, at the point you blow the air horn?

D. Moore · 08-10-2021, 07:47 AM

Thank you both for replying. Yes I agree I am stuck in that purgatory between chassis and coach manufacturers. I am taking the coach up to REV(fleetwood) in Oregon, which has a freightliner service center located within a mile also. Maybe I will bounce back and forth until someone fixes the problem.

Regarding the tank air pressure when I sound the horn, they are both at normal around 115.

jaearhart · 08-10-2021, 07:15 PM

Hopefully you get to the source of this problem. I'll be watching for your response of the final outcome . Good luck .

D. Moore · 10-25-2021, 03:05 PM

Ok! I'm not sure anyone cares but I will post this info in case some other poor soul encounters my problem and the ultimate fix.
As i said I went to REV in Oregon. This is a good service center with good staff. They never really identified the problem but unplugged and replugged my harnesses, did a hard reset on the leveler panel and the system worked as it should ..... until we moved about 30 miles to a new campsite. Then, it was the same problem: Powergear would not recognize my parking brake on until I tapped the air horn a couple times. Called back and the service advisor suggested the powergear control boards. Frustrated I said I'm heading 1000 miles home and I will have a local tech check that out.
But the RV gods intervened! (is there such a thing?) On the way home I got a radiator hose leak and took the unit to Freightliner for repair. I mentioned the air brake switch alarm, and during their repair the tech had to hit the horn to open the rear slide to access the radiator hose, This led the frieghtliner tech to run a diagnostic check and eventually found that an 80 pin communication connector located on the bulkhead(right under the air horn!) had not been seated properly and damaged pins were causing misreads. He unplugged, repaired and replugged. All is well! Evidently blasting the air horn either vibrated the connector enough to allow the electrical connection or perhaps sent some electrical charge thru the affected plugs.
What a blessing to use my jacks and slides without having to wake the whole campground up with an air blast. So far so good and it was worth the trip to finally solve this problem.

For folks with a freightliner chassis this connector plug is up under the dash behind the air brake switch. Accessed thru the inside of the coach. Not easy to get to but what is in a motorhome? If you took the time to read this- Thanks and happy motoring!