'Master Caution' alarm at FL340

[Doug Pelton 1]

737-800 NG    

 

KIAD - KMSY:  Yellow flashing alarm started at @ FL340...beeep...beeeep...Alarm usually comes on after reaching Cruz, I think.

 

FMC loads, flaps, etc okay at take off. MCP functional.

 

Unable to locate any red flashing alerts on Main panel or upper panels.

 

Thanks for input.

 

Doug Pelton

[Cpt DePaola 3]

Did you set the cruise altitude in the pressurization and a/c panel? If not that alarm is for cabin pressurization.

[Lairyliam 17]

Im not a pro, pilot, or an expert on this, but whats the FO Caution panel say? i wonder if its Air Cond... if so you need to check the cruise alt on the overhead. Depending on how i set up, (with FS2Crew) sometimes it doesnt get set, and the plane thinks the cabin should be waaaay lower than i would want it to be.

​Good luck.

​Hope im barking up the right tree for you!!

​Liam Reynolds

[Doug Pelton 1]

Did you set the cruise altitude in the pressurization and a/c panel? If not that alarm is for cabin pressurization.

Will double check..thanks!

Im not a pro, pilot, or an expert on this, but whats the FO Caution panel say? i wonder if its Air Cond... if so you need to check the cruise alt on the overhead. Depending on how i set up, (with FS2Crew) sometimes it doesnt get set, and the plane thinks the cabin should be waaaay lower than i would want it to be.

 

​Good luck.

 

​Hope im barking up the right tree for you!!

​Liam Reynolds

Liam, thanks. The FO side wasn't showing any alarms. WIll check other suggested. 

[DeltaMikeKilo 19]

Hey Doug,

 

By any chance do you have the crew alertness monitor enabled? Sounds like it could be that. If you press any button in the flight deck it will reset. You can also disable this function in the FMC options.

[Doug Pelton 1]

Hey Doug,

By any chance do you have the crew alertness monitor enabled? Sounds like it could be that. If you press any button in the flight deck it will reset. You can also disable this function in the FMC options.

Darren...will look at this as well. Thx

[FishermanIvan 110]

Hey Doug,

 

By any chance do you have the crew alertness monitor enabled? Sounds like it could be that. If you press any button in the flight deck it will reset. You can also disable this function in the FMC options.

AFAIK, there is no CAM in the NG.  Just the 777.

[DeltaMikeKilo 19]

Oh, totally skipped over the first line in his post in my eagerness to help. Nevermind THE CAM then Doug.

[Doug Pelton 1]

Im not a pro, pilot, or an expert on this, but whats the FO Caution panel say? i wonder if its Air Cond... if so you need to check the cruise alt on the overhead. Depending on how i set up, (with FS2Crew) sometimes it doesnt get set, and the plane thinks the cabin should be waaaay lower than i would want it to be.

​Good luck.

​Hope im barking up the right tree for you!!

 

​Liam Reynolds

Overhead Altitude display showing only dashed in both displays. Can't enter.

[738NGFREAK 1]

So most probably both CPC have gone nuts somehow, therefore you get the cabin alt warning horn.

You need to switch on manual and try to set th cabin pressure by your self or try to switch back to auto. 

[Doug Pelton 1]

 

 

So most probably both CPC have gone nuts somehow, therefore you get the cabin alt warning horn.

You need to switch on manual and try to set th cabin pressure by your self or try to switch back to auto.

 

I tried both manual ...auto.. Can't input altitude. At Fl340 right now. Turned off the aural alarm from the overhead.

[Budbud 227]

Hello, can you post a screenshot of the overhead panel with a close view on the pressurization panel?

[Doug Pelton 1]

Hello, can you post a screenshot of the overhead panel with a close view on the pressurization panel?

I'll do that tomorrow!  Doug Pelton

[Doug Pelton 1]

I'll do that tomorrow!  Doug Pelton

Couldn't replicate problem in the air. Started from C&D ...seems the alarm comes on after the APU is on ...engines running....but I forgot to switch on the APU generators. That changed the dashes to numbers in the overhead!  Doug Pelton

[Farlis 2,276]

Overhead Altitude display showing only dashed in both displays. Can't enter.

 

Then you probably forgot to set your cruise altitude in there while still on ground.