M923 WO/W Park Brake Lever electrical issue

[Chief22]

I have a 923 that when the park brake hand lever is in the up position and engaged the dummy light is off on the dash and the buzzer is on under the dash on the drivers side. When the park brake lever is down in the released position the dummy light comes on and of course the buzzer still stays on. Both are done with full tanks of air. Switch in hand lever seems to work, just working backwards and the buzzer never go's off. Just replaced the Haldex module above the center front axle due to the fact of dead short and blowing 15 amp fuse and ABS light staying on, but that has been cured and self checks now. Just got this issue with the parking brake lever. Any suggestions guys and gals?

 

[Suprman]

There are 2 warning lights that share the same buzzer. One is low air and one is the parking brake engaged light. If you lower the parking brake and the dash light for the parking brake engaged is still on and you hear buzzing then chances are the switch in the parking brake assembly is bad or at least out of adjustment somehow. If when you lower the parking brake and the low air light and alarm stay on this is a different issue probably not related to the parking brake. There are 2 air pressure switches one on the primary and one on the secondary tanks. These have been known to go bad.
Will

 

[Chief22]

Superman, the low air light has never worked but the park brake does and like I said it comes on when the hand lever is lowered to its released position. Ya I know it's crazy and working backwards,lol. But that little green box on the drivers side kick panel side wall has never shut up, unless you unplug it. I did notice a burnt spot on the bottom of that buzzered box as if it has gotten hot on the inside. What is the proper name for that whistling box? I do know it controls the light on the dash for the park brake in conjunction that whistle sound that drives you nuts.

 

[Suprman]

Sounds like a bad warning box they are available. Try one of the members selling parts in the classifieds several are parting trucks
Will