RV Repair: 12 volt problem troubleshooting, propane burner, norcold refrigerator

Question
Hi,

Thanks in advance for taking this question.

I'm having a 12v problem.  The refer doesn't turn on, and the lights dim or won't turn on sometimes.  When the lights won't turn on, after I flip thhe switch I hear a loud click which seems to come from the battery box, or an alarm sound--not as lod as a CO alarm.  When the lights do turn on, I don't hear anything.

HISTORY:     10 months ago , I removed the fan blade and motor from the power fan to clean mold on the fan box.  I did not replace the fan blades and motor, but wrapped the wires I had cut I tape.   This didn't seem to cause a problem at the time.    Two months ago the Norcold refrigerator (NOT one of the recalls) said "lo dc" on the display, then later in the day it got better and the regular power indicator was on the display.   Everything was fine for a while.  Four days ago the CO alarm went off seemingly for no reason.  There is no CO around, and I read that a low battery can cause a false alarm.  I removed the alarm.  The next day I put the alarm back and it did not go off.  The next day the refrigerator was off.  It was set in "auto" even though I have the propane shut off. I flipped the circuit breakers on and off, unplugged the ac cords and 12v cords, verified the ac outlet for the fridge is working, verified the fuse on the control panel is good, and verified the battery had water and good connections, and later plugged the cords back in.  The refridge display came back on, but it wouldn't cool even when I switch the controls to AC.    Later the display stopped working but a dim "AU" flashes once every 20 seconds (this fault code is not in the manuals).  I can hear what I think is a clicking from the lighter during a gas lockout every few seconds when the fridge is plugged in.  Still the propane cans are turned off (because propane gives me asthma).  When I unplugged the AC and 12v from the fridge, the propane burner clicking stopped.  At first the 12v lights wouldn't turn on.  But after 24 hours withe fridge unplugged the lights were fine. Then I plugged the fridge back in just for a few minutes to check it again (it didn't work), but after I unplugged it, the lights won't go on again!

I know this is a lot of info, but I wanted to give all the data.  Does all of this taken together sound like a bad battery, a bad converter, a bad circuit board on the fridge, a bad element in the fridge, a short in the 12 v from the cut wires in the fan--or something else?

Thanks!

Answer
Do you know how to use a multimeter?  You can get one for $5 if you look around at hardware stores, cheap tool stores, auto parts stores, etc.  Once you get one, set it for DC Voltage and check your battery for 12.6V.  I think your battery is gone.  Also check to assure your tow vehicle is charging the battery.  

If not the battery, I suspect the fridge itself is the problem.


Two repair manuals I found with some specs and trouble shooting:

http://bryantrv.com/docs2/docs/Nseries.pdf
http://www.gasrefrigeration.net/nor_techdata/Opmanuals/owners_1200_621823d.pdf

Here is an excerpt from the second repair manual:  

Set the controls to Automatic mode operation:
- Push the ON / OFF button to turn the refrigerator on.
- Push and hold the MODE button until the letters “AU” show
in the center display and then release.
- If 120 volts AC is available to the refrigerator:
- The letters “AU” and then “AC” show in the center
display.
- After ten seconds, the “AU” and then “AC” go off and
only a green power ON light remains.
- This means that the refrigerator is operating on AC
electric.
- If 120 volts AC is not available to the refrigerator:
- The letters “AU” and then “AC” show in the center
display.
- After five seconds, the “AU” and then “LP” show in the
center display.
- After ten seconds, the “AU” and the “LP” go off and only
a green power ON light remains.
- This means that the refrigerator is operating on
propane gas.