Community Forums

ronlad · 07-31-2016, 04:05 PM

I own a 2006 holiday endeavor 40' ... the pac brake stopped working on the way home last trip. checked fuse, relay and took apart pac unit and cleaned and lubed to ensure butterfly is operational. still not working. switch lights up but no 5th brake light or braking ...any ideas

palehorse89 · 07-31-2016, 05:13 PM

The Coach has to be above 5 mph in order to activate it.........are you moving when you are trying to see if it is working?

ronlad · 08-01-2016, 01:38 PM

the pac was working on my last trip home, it stopped working en route to home.
i have replaced both circut breakers and 20 amp fuse . usually when i switch on the pac...the 5th brake light lights up, that is no longer working, nor is the pac brake

palehorse89 · 08-01-2016, 04:16 PM

Quote:

Originally Posted by ronlad

the pac was working on my last trip home, it stopped working en route to home.
i have replaced both circut breakers and 20 amp fuse . usually when i switch on the pac...the 5th brake light lights up, that is no longer working, nor is the pac brake

You are going to have to take a multi-meter and do some checking, starting at the fuse(Power source) and do some troubleshooting with the meter, checking for 12 VDC.
The relay's will be a bit more troublesome to trouble shoot, as they are looking for a signal from the Allison/Cummins ECM's to activate the Pac Brake......
To start with, make sure there is 12 VDC at the fuse supplying power.

barmcd · 08-02-2016, 06:32 AM

Does the Allison shift pad go to 2 when you engage the Pacbrake?

ronlad · 08-02-2016, 03:11 PM

no the trans retarder will not work as wel,l it usually goes from 6th to 4th when the rpms are within limits and the ecm sends signal to exh brake and trans.

barmcd · 08-03-2016, 06:32 AM

it sounds like you have an issue pretty close to the front of the process. I'd check the brake switch first. DO you have a foot brake or switch on the panel?

jpharley · 08-03-2016, 07:40 AM

Has the compressor gone out on it? We had a Pac Brake on a dually truck and the compressor that worked with the brake went out and we had to replace it. Not sure if it works the same on a motor home.

ronlad · 08-03-2016, 02:02 PM

called northeast cummins, they seem to think... a broken wire at the ECM plug or a bad ECM, 'im sure it will be costly

barmcd · 08-03-2016, 03:32 PM

Quote:

Originally Posted by jpharley

Has the compressor gone out on it? We had a Pac Brake on a dually truck and the compressor that worked with the brake went out and we had to replace it. Not sure if it works the same on a motor home.

The Pacbrake would use the same compressor as the air brakes and suspension no? A dually would have a specific compressor because it doesn't have air brakes or suspension.

Dutch Star Don · 08-03-2016, 04:26 PM

"ronlad".....Do a thorough check of the fuses in your run bay. You have the small box(es) under the large fuse box that have fuses for the pacbrake. Also, there is another black box for the Allison.....if you remove the lid, there are several relays inside of that box. I believe there is one or two there for the exhaust brake. The second photo is of the Allison box, you have to remove the screws.

I spent a lot of time running down an exhaust brake issue on my Diplomat.

Ray,IN · 08-03-2016, 10:06 PM

Try phoning Pac-Brake service, support, and troubleshooting customer service.
This is their sole mission.

barmcd · 08-04-2016, 06:22 AM

Since it appears none of the functions work, it should not be difficult to find out where the issue is. I'd start with the switch and see if you have 12 volts at one contact and continuity through it. If you do, then the problem is down stream of the switch so you'd look at the solenoid next. If you don't then the problem is up stream and you go look at fuses and relays.

RV735 · 08-04-2016, 06:44 AM

We also had the same problem, the exhaust brake would not activate. After mush thought and inspection I traced the problem to wire in the dash going to the exhaust brake switch was strained and pulled away from the switch. I re positioned the wire reattached to the switch and it has worked for 3 yrs. Hope yours will be as simple!

Safe Travels and THE JOY IS IN THE RIDE