I have several questions from our first extended camping trip. On the trip, my dash gauge reading dropped down from the normal 13.5-14 to 11.5-12.00 volts. At the same time the check engine alarm began to sound. My generator was already running along with the Aqua hot. After about an hour, with no voltage change, I switched the boost switch on and immediately the dash voltmeter bumped up to 13.5 again. What is causing this voltage drop? Does my dash gauge only monitor the engine battery power? Without the boost switch on, is my gen powering just the house batteries?
David Blackford
David,
1. With that low of voltage you getting close to the ECM shutting down
2. I am surprised it ran that long before the engine at least started missing
3. Could be a bad connection on the alternator sense wire, a bad breaker on the sense wire, failing alternator, failing battery isolator. (first things that comes to mind)
3a. FYI research the DUVAC system that your coach came with.
4. Yes
5. yes.
Mike
Check your alternator to see if it is putting out.
My dash monitor does not read correctly. When I read up on issues I have had with my gv320 I usually come across something one of the members have already figured out that is helpful to me. Someone suggested this item that I keep plugged in when running down the road.
Amazon.com: Palumma 24W/4.8A Dual USB Car Charger, 12V to USB Outlet with... (https://www.amazon.com/Palumma-Charger-Adapter-Display-Battery/dp/B0773BYS6P/ref=sxts_sxwds-bia-wc-nc-drs1_0?cv_ct_cx=12v+usb+charger&dchild=1&gclid=CjwKCAiAxeX_BRASEiwAc1QdkWKRYD0yT4EAI3UmEBcS1xEug0kVEZREGfYCIj3Rlh42MRkBafJt7RoC_bQQAvD_BwE&hvadid=409959113740&hvdev=c&hvlocphy=9014154&hvnetw=g&hvqmt=e&hvrand=17237865545190290517&hvtargid=kwd-19594273647&hydadcr=19105_11276260&keywords=12v+usb+charger&pd_rd_i=B0773BYS6P&pd_rd_r=b2ee9b3d-a918-4843-9175-00bccbf25b6b&pd_rd_w=GCnMO&pd_rd_wg=5aTM0&pf_rd_p=a64002b9-9c26-4361-b8a1-b0f5a4835670&pf_rd_r=D421BNJPK4630B6WVEXB&psc=1&qid=1610215538&sr=1-1-38d0a374-3318-4625-ad92-b6761a63ecf6&tag=googhydr-20)
I have 2–12v plugs on the dash. My top one reads the voltage of the house batteries.
And the bottom plug reads the voltage of the chassis's batteries
Running the generator does not charge the start batteries as the coach was originally configured. Switching on the boost switch connects the start batteries to the house batteries which makes your start battery voltage go up.
Start with a sense wire change, the connectors at either end fail. The sense wire lets the alternator know the start battery voltage. Test the output of the alternator. A bad sense wire, bad connections, a failing diode based isolator and any of the connections from the alternator to the start batteries are suspect. Check and clean every battery post and cable. Make sure you batteries are connected properly.
Easiest place to start your troubleshooting is at the BATTERY ISOLATOR.
With engine at 1,100 or so RPM, check voltage on the middle stud (from alternator B+ terminal). Should be in the high 14's. Check voltage at the two outer terminals (one connected directly to chassis batteries, the other to the house batteries). Each should read about .7 VDC less than the center stud. 13.5-14,2 is fine.
Let us know what you find and we can direct you to the "next easiest place to check".
Thanks for all the responses and helpful direction. I now have a game plan ready. I will add to this post after I've made some checks.
Dblackford