Our annunciator (I call it the "Irritator") is sounding incessantly. I know this is not uncommon - I have read all the old posts - just looking for any fresh ideas on how to fix.
Yesterday, I decided to take the coach out for exercise after several weeks of inactivity. Starts right up, good oil pressure, air pressure comes right up to 120psi, HWH "travel" light comes on. Everything appears to be normal and correct, but the warning chime is still screeching??? I tried everything I could think of to silence it. I cranked the TV antenna up slightly, and the red ANT UP idiot light comes on - crank antenna down, ANT UP light goes out. Alarm still on. I cycled all the HWH up and down switches - all air bags and valves work perfectly. Transmission goes into drive and reverse just fine, parking brake releases normally. With the parking brake released, all warning lights on dash are out and all the mechanical gauges are within normal range, but warning chime is still sounding.
I decided to go ahead and take the coach out, hoping the problem would cure itself. (I used the volume adjustment screw to mute the alarm) We drove a 50 mile loop with varied speeds. Stopped and got the propane tank topped off. Ran the generator and both roof AC units while driving. Shut off and restarted engine several times. During the whole drive, all mechanical gauges showed normal, transmission shifted perfectly, and everything worked fine. Checked engine and trans oil levels when we got back - both are correct. But the #%@&*)$&#% alarm never shut off.
Question: How can you have a audible warning alarm WITHOUT any warning lights illuminated? According to my "Digitron 1300 Alarm Module" wiring diagram (A-4749), they are both tied together. Any sensor input (even if false) that triggers the alarm should also light the appropriate idiot light. My wife said, "Perhaps a bulb is burned out". I pulled the warning light bar out of the dash, but I don't see anything on it that looks like a bulb. It is just a sealed circuit board with a bunch of solid state devices stuck on the back.
Anyone ever had a warning light fail, or had to replace a warning light bulb (if there is a bulb)?
I tried re-seating the connector on the back of the warning light bar - didn't help.
I'm stumped - hoping someone will have a brilliant suggestion.
A well placed piece of tape ;)
Mine also sounds with turn signal lever on. You covered all the other reasons it should sound.
Do you have a wiring diagram that shows how all the inputs connect to the annunciator and a voltmeter? I would check them one by one to find the offending input.
I just thought of a possibility. Perhaps one of the inputs is "on" enough for the annunciator but not "on" enough to drive the light to visible brightness. This could be caused by dirty contacts (and a real reason for the alarm to sound and light to light) or caused by leakage across a switch, with enough drive for the sound but not for the light.
One way to check for this would be to measure the voltage across each of the unlit lamps. One of the "off" lights might actually be getting a low voltage.
Agree with Tom. Check and clean the contacts-- antenna up (or just replace the switch (couple of dollars). Same for engine alarms like temperature and oil pressure. I use 1000 grit sand paper to clean and then coat with silicone di-electric grease.
Chuck
We had a air pressure sensor go kaput and caused the alarm to sound. Ours was located down by the steering gear box on the air lines that feed the brake treadle valve. Every thing else was working just fine and we almost never found the problem.
Pamela & Mike
OK, some good ideas here...not the brilliant all-in-one turn-key solution I was hoping for, but helpful.
Tom: I do have the wiring diagram. I will try checking the pins on the warning light bar connector to see if I can detect which circuit is "active". I guess it is possible that the alarm could be triggered without the matching warning lamp being lit, but it doesn't seem very logical. I would think a mechanical vibrating noise maker (especially one this loud and obnoxious) would require more power than a tiny light bulb (or LED), but I may be wrong.
Brett: I wil try cleaning the electrical connections on the oil pressure switch, the water temperature switch, and the antenna up switch.
Mike: When your air pressure sensor malfunctioned and caused the alarm to sound, did you also get a AIR PRESS warning light on the dash?
Mine, in my 93 U240, went off one time when snow sludge triggered the leveling sensors. James Triana suggested that I cut the blue wire to the enunciator to silence it (and my DW) until I could get to a service center. This of course disables all safety features but heck they are disabled already if it is squealing all the time anyway.
I don't need to cut any wires to mute the alarm. Ours has a little screw on it that is supposed to be a volume adjuster, but actually it is just "On" or "Off", depending on where I turn the screw. So at least it is easy to kill the noise until I figure out what is causing it.
Chuck,
No, just got an alarm no light. After hunting there was 1 switch for the light & 1 for the buzzer. That was on our '92. It may have been an add on by the previous owner.
Pamela & Mike
You didn't specifically mention alternator output. Is your dash voltmeter showing its normal reading?
Chuck,
Seems that whenever I would get strange or illogical indications with 12volt systems on planes, boats, etc. it was usually a grounding problem somewhere.
I had an old post with the same problem. I tracked my problem to the ant up circuit. No light unless the ant was up, but beeping all the time. I replaced the switch on the ant - problem solved, until I siliconed the wire connections on the new switch. Beeping was back. It is now a problem to be fixed on another day. I disconnected the wires at the switch. I think it must be a problem FT knows about, because on my wiring schematic it has a note that says " ant causing beep,no light" the note was not added, but on the original copy. Mark
I had the annunciator beeping for a couple days after my electronic pressure guages failed. I found it on the left side of the dash (not hard to find since it was beeping). I wird in a switch to shut it off. Mine also has a twist top that opens or closes the openings in the top and adjusts the volume somewhat.
I miss the turn signal beeper, still trying to figure out how to wire that up.
Roger