psandoz Report post Posted September 28, 2018 I saw several others discussing phantom air brake alarms on this site. We have a 2000 Damon Ultrasport on a freightliner chassis. Air pressure is fine, gauges read 120 psi +. Mechanic has checked all fluid levels, everything is ok. When the coach is in drive, air brake off, the air brake alarm starts beeping 10 seconds after engaging transmission. Does the same in reverse. Same alarm as when coach is in neutral with no brake, air brake alarm warns that the parking brake is not engaged. No alarm when coach is in neutral and air brake is in park position (as expected). I can't find a schematic for the coach to show if there is a low pressure alarm. Looked at the 2 air tanks and even bleed them down to zero, no change. Pressure came back to 120+ psi, brakes work fine, airbags work fine. Just seems there is a faulty low pressure switch connected to the transmission? Appreciate any suggestions or experience other members may have. Share this post Link to post Share on other sites
wildebill308 Report post Posted September 29, 2018 Welcome to the forum. Does it say it is a brake alarm? or just the alarm? Bill Share this post Link to post Share on other sites
dickandlois Report post Posted September 29, 2018 15 hours ago, psandoz said: I saw several others discussing phantom air brake alarms on this site. We have a 2000 Damon Ultrasport on a freightliner chassis. Air pressure is fine, gauges read 120 psi +. Mechanic has checked all fluid levels, everything is ok. When the coach is in drive, air brake off, the air brake alarm starts beeping 10 seconds after engaging transmission. Does the same in reverse. Same alarm as when coach is in neutral with no brake, air brake alarm warns that the parking brake is not engaged. No alarm when coach is in neutral and air brake is in park position (as expected). I can't find a schematic for the coach to show if there is a low pressure alarm. Looked at the 2 air tanks and even bleed them down to zero, no change. Pressure came back to 120+ psi, brakes work fine, airbags work fine. Just seems there is a faulty low pressure switch connected to the transmission? Appreciate any suggestions or experience other members may have. What Leveling system is used on your coach ? When the fluid level drops on hydraulic leveling systems - there is an alarm indicating a low fluid in the leveling system. Did the Mechanic check the leveling system fluid ? and is the sensor float adjusted properly ? The other item to check on is the VDU Module. They have had issues with the solder connections that can cause erratic pressure readings and air pressure alarm to go off. The mentioned module was used on the model year of your freight liner chassis. They can be repaired in many cases - it you know a good electronics tech. Replacing them can run well over $ 1000.00, plus the labor. Rich. There are no Air lines connected to the Transmission on any of the Drawings I have for the freightliner chassis. There is(are) some wiring circuits that cause an alarm to sound when the transmissions are in gear when the park / air brake is engaged, or in some cases where a slide is not in. The coach builders add safety alarm systems that are not part of the original chassis. Share this post Link to post Share on other sites
