Community Forums

Dieselboy · 02-08-2023, 08:22 PM

Hi all. I was replacing the head unit for the display of my camera system of my Navigator. Something has gone wrong and there is now a humming noise coming from behind the dash where the old monitor (Kenwood KVT M707) was. I didn't plug anything back in with the wiring harness. There appears to be a center HVAC system directly being the temp controls, gps screen and camera monitor. The noise seems like it's in that general area. I killed the power to the whole coach and it obviously went away. Came right back when I powered back up. Stays on even with no accessory switch or ignition in the on position.

Any thoughts? I'm tired now and it's boggling my mind.

shootist · 02-08-2023, 08:47 PM

Is your ac heat defrost select switch on off?

vito.a · 02-08-2023, 10:21 PM

Wow, that is a beautiful coach!
Is your Aqua Hot furnace on? There is an Aqua Hot heat exchanger in the center dash.

Dieselboy · 02-09-2023, 02:26 AM

Quote:

Originally Posted by shootist

Is your ac heat defrost select switch on off?

No, it’s in the off position.

Dieselboy · 02-09-2023, 02:27 AM

Quote:

Originally Posted by vito.a

Wow, that is a beautiful coach!
Is your Aqua Hot furnace on? There is an Aqua Hot heat exchanger in the center dash.

No. That is also off. And thank you for the compliment. I just can’t seem to find it.

Bill767 · 02-09-2023, 04:37 AM

I hope someone has an answer as I have exactly the same sound in my dash, but it is intermittent. On at least 50% of the time, but I haven't found it or figured out what causes it to come on.

Dieselboy · 02-09-2023, 07:27 AM

Quote:

Originally Posted by Bill767

I hope someone has an answer as I have exactly the same sound in my dash, but it is intermittent. On at least 50% of the time, but I haven't found it or figured out what causes it to come on.

Mine is constant and gets slightly louder if the key is in the "on" position.

Dieselboy · 02-09-2023, 09:31 AM

Quote:

Originally Posted by Bill767

I hope someone has an answer as I have exactly the same sound in my dash, but it is intermittent. On at least 50% of the time, but I haven't found it or figured out what causes it to come on.

I found my problem. There is a small speaker behind the gauge cluster. I will be replacing it with a similar small speaker that isn’t humming.

YC1 · 02-14-2023, 09:11 AM

Off the wall thought here without more information.

A monitor system may have a microphone/speaker setup so you can listen to someone outside helping give you directions for backing.

Again, not knowing how your old setup was there could have been a plug for an audio feed to some amplifier. The speaker gives me a clue for this idea.

A non terminated plug can cause all kinds of noise in an amplifier/speaker setup.

The changing volume or sound when the key is turned could be a change in voltage do to all the loads on the power at that point in time.

Just replacing that speaker shown (I know it is not the op's), would not likely solve the humming issue.

Speakers by themselves just have no way to hum. They need input voltages. Basic speakers are really dumb animals with just a few components. A coil of wire and a permanent magnet.

If you find a plug that was left dangling from changing a monitor, your fingers touching the plug end may cause the hum to change.

In any case, make sure it is not touching anything and if it is, tape it up.

The other thing could be a ground loop issue and those can be a real bugger to sort.

Lots of pictures from the area where things changed could really help.

Iceclimber · 02-15-2023, 10:16 AM

My coach had that very speaker and I disabled it. That doesn't look like an alarm.

153stars · 02-15-2023, 02:03 PM

YC1 hit on the head rear cameras had mics. Does speaker have tiny amp board the feed power must be from somewhere. I see a fuse wire but can't tell if attached. Some coaches had multi-alarm module with several alarm feed wires. I think each is then given different pulsed tone to identify the alarm but it was tied to small piezo speaker or buzzer about 1" total around.