Community Forums

jaminman · 02-01-2014, 03:22 PM

Hi all, have been reading for some time and have gained much knowledge. Decided to post a problem I have been having. Have a strange warning sound coming from the dash. It is not the levellers as that is a different sound. I recently changed my coolant, serpentine belt, ac belt, thermostat, and filter for hydraulic reservoir. I had a slight leak from a hose and the coolant sensor came on very faint so I decided to do all the rest, as it was due. Since then there appears to be the same sound only now it is sometimes loud and sometimes faint. Disconnected the sensor on the surge tank and it still continues. If it was a bad sensor would disconnecting it cause the alarm to stop? I know sometimes it still does not. Any ideas would be greatly appreciated. I have a 2005 Holiday Rambler, besides the coolant level and hydraulic levellers is there any other sensors?

1ciderdog · 02-01-2014, 03:26 PM

I had a strange noise and it turned out to be the volume control on the back up camera had been turned up when my spouse was cleaning the screen. Hope it's simple like that.

jaminman · 02-01-2014, 03:45 PM

It is definitely coming from the dash. Not the back up monitor. Seems to be on the left drivers side near the window. I am guessing that is where the warning buzzer is. It also seems to get louder as I drive longer and then go higher in pitch. Checked to make sure all my kids are accounted for just in case, lol

94-Newmar · 02-02-2014, 05:58 AM

I am currently working on an 05 Monaco Cayman and in the list of things to fix, this exact problem is one of them. A very faint yet distinguishable single tone alarm right under the dash. It almost sounds like the low air warning tone but I bled the air to get the warning light and alarm to come on, which it did, and let it air back up, warning light went out and alarm went away but there is still another very faint warning somewhere under there. I will update the thread when I get around to finding it, please update this thread if you find yours too.

Clayobx · 02-02-2014, 10:31 AM

Interesting, this is going to be a learning experience. Please keep all of us posted.

jaminman · 02-02-2014, 10:33 PM

My MH is a 2005 Neptune, which would be the Monaco version of the Cayman, would appreciate any further insights. Yes it sounds like a very faint low air warning. It is sometimes louder and then softer. My coolant did get low because of a loose clamp, and I decided to change coolant. I do not have a low coolant light only an audible sound on the dash. Could the ECM be giving me a false reading letting me know it is low? I unplugged the sensor on the surge tank but still have the noise! Yesterday I started the MH and there was no noise, today there was, then later today there was not! Have a trip coming up and want peace of mind, Peter

wa8yxm · 02-03-2014, 07:14 AM

I had one after-market device on my MH (One I had to fix last week in fact) that has a sonalert in it (Warning noise maker) I had to cut out since it kept alarming due to the manufactuer and GM haing different ideas of what is and is not proper voltage.

One cause of this kind of alarm is moisture.. It can get onto a sensor or onto the wiring to the minitor and sound the alarm even if there is no alarm state.

jaminman · 02-03-2014, 10:44 AM

I called Monaco and they said there are only three areas that could cause a alert on the dash; the coolant level sensor, low air pressure or brake sensor, and the hydraulic levellers sensor. 4 weeks ago the hydraulic sensor did go off and I topped it off (was a different noise) and it left. They also said a sensor malfunction would not record on the ECM. They said there is no alert signal for seat belt not fastened, not required by law, so that illuminates that possibility. I asked if I could disconnect the sensor and hot wire it across to see if it stops, and they said that would be the way to do it. Would appreciate anyone else that has an opinion or idea?

Dutch Star Don · 02-05-2014, 12:29 AM

When we purchased our 2005 Monaco Diplomat new, we drove it home from Fresno to Los Angeles during the summer. I noticed that every time we started to climb a small grade, I would hear this very faint alarm that would build. I stopped the coach and called Monaco tech support.

They told me the following: Monaco adds a secondary temperature alarm/buzzer. It can act up and sound even when the coach is not warm/overheating. They told me to pull the dash plate (above instrument cluster) where I located the alarm and disconnected it. This was just an add on by Monaco and wasn't necessary since Cummins had it's own alarm and would derate the engine if it got hot.

There is also another problematic alarm that many identify as being the jack alarm. This alarm sounds when you put the coach in drive and release the Parking Brake. You get the low air alarm, but no lights indicating an issue. Once this starts happening, the problem persists. This issue is caused by a pressure switch under the Parking Brake switch. The pressure switch is made by Nason and is really only available (because there are so many models of it) through Monaco, about $50.00 shipped.

jaminman · 02-05-2014, 09:39 PM

Do not think it could be the park brake as it often sounds as soon as I turn the engine on prior to releasing the brake, although often very faint and then sometimes not at all. I started the motorhome today, and it has been very cold and it was loud almost like the low air buzz noise. I noticed when I put my foot on the accelerator the head lights got brighter? After 5 minutes of idle the buzz noise was hardly noticeable (very faint in the background) and the lights stayed the same brightest when the accelerator was pushed. Could it possibly be a bad or low battery that could cause a buzz, when it does not have a full charge and when the engine runs for a bit it charges them more, hence the drop in noise level? The gauge on the chassis and house battery level said it was 13.49, with lights on, and 13.90 with them off, is that normal?