Exhaust brake, and cruise control brake cancel function not working

[Carl Boger]

We drove down to Charleston SC today for a long weekend and everything was functioning correctly.  About 200 miles in I stepped on the brakes to get the cruise control to turn off, and it didn't.  I slammed on the brakes harder and the cruise control turned off.  I hit resume a little later and it was back on on cruise.

A few miles later I had to slam on the brakes again but the cruise would not disengage.  I turned off the cruise control and turned on the exhaust brake. 

The first time I let off the accelerator pedal the exhaust brake came on momentarily then it went off and did not activate any more.

I am assuming that these two issues are related.   Does anyone have a good place to start troubleshooting this.  I have not checked to see if I have brake lights yet, but will likely do that tomorrow.

I am not super worried as I don't need cruise or the exhaust brake to get home.  It is also raining here right now so I won't be checking things out until it stops.

Thanks for any help

[Steve Huber Co-Admin]

Carl,
First thing I'd check is the brake pedal switch as the symptoms sound like it is out of adjustment. It should be located under the dash on the brake pedal arm.
Enjoy Charleston if you can put up with the traffic. We were there last week.
Steve

[Carl Boger]

Thanks Steve, will check it tomorrow. Traffic coming in was stop and stop!  40 minutes to go 4 miles.  I am in James Island Campground now.  We may drive to Folly Beach, but for $10.00 a head we will take the shuttle into Charleston.  Last time I drove in from here I paid $14.00 for parking and it took me 20 minutes to find a parking spot!

[Carl Boger]

Steve,

I don't have a brake pedal arm.  The brake pedal is mounted to the floor.  Probably not going to crawl under the coach in the sand to try to find it on the under side. 

[Eric Maclean]

Carl
I'm assuming your coach is air over hydraulic brakes .
The brake light switch is air operated and I believe it is mounted up under the drivers floor near the treadle valve .
First check to see if the brake lights are working.
Next go to the coach assist wiring diagrams for 1996 patriot and look at the diagram for the cruise/ brake light/ exhaust brake as they are all tied together via a series of relays.
 it sounds to me as if you have lose the brake light input ( bad pressure switch) or one of the relays is not functioning as designed
( Bad relay or wiring connections )

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Hope this helps
Eric

[Carl Boger]

Thanks Eric,

I suspect you are spot on as usual.  It is a air over Hydraulic system.  We were to busy being on vacation today to get to it.  Not sure if tomorrow will be much better, but at least I have somewhere to look.  I may be able to get to the switch through the front cover and not need to lay in the sand.  Brake lights are not working so hope to fix before heading home.

There is a switch near me in stock 'hopefully' so I may pick it up in the morning just in case.  Best case I have a spare if it is just a loose wire or something.

[Carl Boger]

Eric,

Seems you were right yet again.  The 4th store that I went to actually did have the part in stock.  I am not heading back until Monday, but I thought I should get the part today since it is calling for rain tomorrow. 

Bought the switch, got the tools out to remove the wires and the whole switch turned as I tried to remove the nuts that held the wires in place.   I thought I should probably reverse course, so I tightened the switch about 1/3 of a turn until it was snug.  Went inside and cranked up the MH and set the fast idle with the cruise control.   I pressed on the brake and the fast idle released, so I am going with this is fixed.

It's not worth it to me to drive 36 miles round trip to return the switch so I have a new switch in the parts bin.

Thanks for the troubleshooting help!  Should be a safer trip back home.

[Eric Maclean]

Glad to hear you got it up and working again ( those switches tend to get loose at the crimp and will blow apart it may be a good idea to replace it when you get home ) I know it's in a nasty spot to get to .