j2a2b2 Report post Posted July 21, 2019 I have a 2016 Jayco Seneca Freightliner M2 chassis. the message center reads "Park brake not set" and alarm sounds after I put it in drive and release the yellow park brake. we just returned from a 400 mile trip last month without any problem. Both slides are in and jacks are up. Anyone have any ideas. Share this post Link to post Share on other sites
jleamont Report post Posted July 21, 2019 Have you tried it in this order: 1.step on the service brake 2. release the parking brake 3. then shift into D? Does it stay on after you begin to move? My alarm sounds if I do it out of the above order, It does silence after a few seconds but it sure gets your attention. Share this post Link to post Share on other sites
huffypuff Report post Posted July 22, 2019 Awhile back I had a bad parking brake release valve. Share this post Link to post Share on other sites
f442485 Report post Posted July 22, 2019 We basically had the same issue. It turned out to be a defective pressure sensor. The sensor is located in the air line at the park brake valve. it was very easy to replace. Mine was a three wire sensor and I understand there is a two wire sensor that was also used. Hope this helps. Share this post Link to post Share on other sites