High Pitch Noise Coming from Electrical Cabinet

[RickyBobby1099]

Hello everyone. I'm having an issue with by 2006 Ford E350 bus. The body is made by Thomas. I do not have an operator's manual for the bus and have no idea what fuses do what.

Tonight, after having driven the bus home 250 miles yesterday, I get in and out the key in the ignition and as soon as I turn it to accessory power, a high pitched ringing starts. Starting the bus completely doesn't stop the noise. This didn't happen this morning when I started the bus.

Above the driver's seat is a cabinet that contains numerous fuses. Attached to one of the fuse panels is an annunciator of sorts. The noise is coming from that annunciator. I have no idea what is causing it.

Additionally, the instrument cluster was acting up. It showed the volts as being maxed out (and when I turned off the bus, the needle dropped to half) and the "brake" indicator light was flashing intermittently even though the parking brake was not engaged.

Any and all help is appreciated!

[RickyBobby1099]

EDIT:

The brake indicator light stopped flashing when I recorded the video.

Here is a link to a video of the issue:
https://youtu.be/p1a0x4xSEgU

[dwood443]

Some type of sensor. Low air. Emergency exit. Door open switch left on. Lots of safety stuff in these buses

[RickyBobby1099]

Thank you for the reply. The bus doesn't have air and the doors were all closed. Starting to pull my hair out with this one...

[musigenesis]

I thought I had posted this comment already, but try taking a video (with sound) of the problem you're having and post it to youtube or wherever, and then link to it here. Somebody will probably be able to diagnose the problem easily then.

[RickyBobby1099]

You did post that last night. I took a video of the issue and tried post g the link to the video and then the entire post disappeard. No idea why.

[musigenesis]

Originally Posted by RickyBobby1099

You did post that last night. I took a video of the issue and tried post g the link to the video and then the entire post disappeard. No idea why.

Ah yeah, your account only had 3 or 4 posts last night so you can't post pics or I guess videos (I think video posting maybe requires the mods to initially approve your account). PM me the link and I'll post it as a comment here and that should work.

Not sure why the mods would have removed my comment as well.

[musigenesis]

Here's your video:

https://www.youtube.com/watch?v=p1a0...ature=youtu.be

That is damned irritating, that's for sure.

[RickyBobby1099]

Thanl you for posting this!

[Willie_McCoy]

Originally Posted by musigenesis

That is damned irritating, that's for sure.

That is the understatement of the week right there!!

[Mountain Gnome]

Is there an inverter in the bus?


The dash gauges are the real clue...

[RickyBobby1099]

Not one that I've installed. Do they normally come stock?

[Mountain Gnome]

Originally Posted by RickyBobby1099

Not one that I've installed. Do they normally come stock?

No, they are not a normal "stock" option. Typically aftermarket.


Perhaps it is the other way around, then. Can you figure out how to disconnect the wiring from the "radio" thing that is making the noise? Does that help the dash gauges?

[RickyBobby1099]

Originally Posted by Mountain Gnome

No, they are not a normal "stock" option. Typically aftermarket.


Perhaps it is the other way around, then. Can you figure out how to disconnect the wiring from the "radio" thing that is making the noise? Does that help the dash gauges?

I'm sure I could figure how to but the gauge issue is intermittent. I'm wondering if the cluster is bad and it's causing the alarm.

[Mountain Gnome]

Not that I know what I'm talking about, but to me that looks like a battery maintainer / solar panel thingy / or large inverter. The buzzing is a warning of short to ground or overvoltage or something.


Can you take a picture of it so we can read what the writing on it says?


What do you mean "annunciator"?
Is this a separate thing? Can your picures identify that better?

[RickyBobby1099]

Attachment 47395

Originally Posted by Mountain Gnome

Not that I know what I'm talking about, but to me that looks like a battery maintainer / solar panel thingy / or large inverter. The buzzing is a warning of short to ground or overvoltage or something.


Can you take a picture of it so we can read what the writing on it says?


What do you mean "annunciator"?
Is this a separate thing? Can your picures identify that better?

The annunciator is the device that's emitting the buzzing sound. That whole panel is what controls the bus and is original to the bus. I'll try to post pictures but the last time I did, it deleted the whole post.

[Mountain Gnome]

Ah, now I can see better, and I agree with what you are saying. Yes, I think the dash gauge cluster may have a problem in it.


Someone with a Thomas bus may know more than me, but I bet the alarm is indicating a short to ground. However, I'm not sure why the voltage gauge is pegged.


Without being there, that's about all I can tell you.


Look for a Thomas Bus owner's manual online if you can and see if that can give you a clue as to what the buzzing alarm means.


Or I'm sure someone else here will come along before too long and be able to tell you.

[RickyBobby1099]

Well it turns out that one of my kids had lifted the handle for an emergency exit window. All of this worrying for such a simple fix 😂😂. Thanks for everyone's input.

[Mountain Gnome]

++++++++++++++++

[dwood443]

Originally Posted by RickyBobby1099

Well it turns out that one of my kids had lifted the handle for an emergency exit window. All of this worrying for such a simple fix [emoji23][emoji23]. Thanks for everyone's input.

Haha. Like I said. Ask me how I know[emoji849]