06' HR Ambassador ISC 330 Boost Alarm

bredden · 09-02-2009, 02:24 PM

When climbing slight grades at normal interstate driving speed, I generate this alarm, which starts off like a cricket sound, then progresses to a full alarm. I first thought it was Power Gear float switch. New float switch installed no joy. It appears to be related to the turbo boost. If managed to under 20psi boost no alarm. In the 23 psi range it will deliver a full alarm. Nothing in the manuals relate to this type of alarm. There are no visual alarm, only audio. Am I missing something. Any suggestions, before taking it over to Cummins.

Rex · 09-03-2009, 01:00 PM

OK is the sound coming from the dash? Have someone else use a plastic hose with one end in the ear and the other probing around the dash area to locate where the alarm is coming from while you drive. I suspect it is the boost gauge itself that is the problem. There is a single 1/4-inch air pressure line going into the gauge. The noise you are hearing may be a malfunction of the gauge or a leak in the gauge or air line causing the noise.

Diplomat Don · 09-03-2009, 01:59 PM

bredden.....While driving our coach home from the dealer (new) we heard the same thing on the first grade we hit. It started as a chirping that was hard to hear and then got louder. It finally would turn into an alarm. Ours was directly related to the temp gauge. It would start to chirp at about 196 degrees and then alarm at a little over 200.

I called Monaco and was told that they had added an additional overheat alarm. They said it wasn't needed because the Cummins alarms would certainly let you know if there was an issue.

I found this secondary alarm under the cover plate on the dash. If I recall it was black, about 3.5" x 1.5" with an obvious buzzer/alarm at one end. I disconnected it and never had another issue.