I am looking for direction to address the following problem - the voltmeter on the dash panel reads 10v, - at best 12 volts when running at normal speeds (1800 -2000 rpm) on my Cat 3208T. Took reading at back of 160 amp alternator and it reads 14 volts. Have the Intellipower system with a 75 amp decal on the charger. I have no problems with starting the engine or driving but the audible alarm under the dash continually sounds indicating low voltage. Lights are normal with no appreciable dimming when idling. I have normally left the coach plugged into shore power to run a/c and keep humidity low when parked. I do find the coach batteries losing water over several weeks but the Run/Store switch seems to operate, at least I hear a click and the 12 v lights and appliances turn off. I just had a belt problem and when I tightened it up to spec the voltmeter raised to 12.4 while I was driving. When night came along and all the lights were on it dropped to 11 v. I would like advice on where to start diagnosing the system to fix this. Any ideas are appreciated.

What does your dvm read when connected to the batteriescompared to the dash voltmeter?

quote:

Originally posted by Tom K:
I would like advice on where to start diagnosing the system to fix this. Any ideas are appreciated.

While this might sound like a simplistic answer, I'll still offer it anyway... anywhere you see a green wire.

Barth had numerous green ground wires on grounding bus bars. These grounds would varnish up/corrode and will lower your voltage.

While I'm not saying your issue is in the side box area, I am saying that you'll need to break out your toolkit and start tightening up some wires and check different areas with a volt meter.

My best guess? Bad ground wire within the dash area, maybe where the bus bar grounds to the tin plate and where that grounds to the bulkhead mount. This is where I found my worst grounding issues.

What happens when you turn on the T-Signals?

Sorry to take a while responding - had to recover from a hurricane. OK the alternator reads 13.8 to 14 volts at 1,000 rpm as does the battery and the battery main on the ignition relay and the ignition switch center post.. The run wire on the ignition switch reads 11.2 - so I am getting a new ignition switch. The dash has three large bundled sets of wires- black, red and green. All the 12v that is distributed connects to the red bundle and the ground to the green bundle. As may be the case with other Regencies there seems to be a good number of various colored wires stashed under the dash leading nowhere. Some are hot with ignition on while others seem dead at all times. I assume these were for the Gillig bus stuff as the chassis cabling is tied up under the drivers feet behind the headlight with a bundle that will fit at least a 48 foot bus. I am planning to replace the switch and then start following wires, even if I have to disconnect each one until I find the load that is causing this problem. I checked each green bus, loosened and cleaned each wire and replaced without any change. Am confused about a load problem as the batteries are all charged and fine. Still looking for any advice or hints.