I've got issues

[DFR]

2007 Fred chassis- Suddenly the starting batteries began going dead in about 5 days of sitting. While installing a braking systen for the Toad, I was laying under the MH on a very humid day. When I reached up and touched the driveshaft, I received a mild shock. I dug out the multimeter and tested for power by sticking the common lead into the dirt next to the MH and touching the positive lead to the frame of the MH. It showed about .2 amps of power going to ground. Question. Where in the heck do I start to try and isolate where this is coming from?

[OneRVer]

Not much help here but I would start looking around the battery compartment. Looking at all of the positive wire's and making sure that none of them are damage and touching the frame. If you have more then one hot wire coming off of your battery post I would remove one at a time and recheck your voltage at the drive line not the current. At least this would help you know which wire is your problem. Like I said not much help but this is where I would start. Good Luck and let us know what you fine.

[FleetMan]

Start pulling fuses and circuit breakers one by one till you isolate the circuit that is hot.

[DFR]

Am I correct in assuming that, since it's the starting batteries and not the coach batteries that go dead, I do not need to check the coach circuits?

[ernieh]

DFR,

If you received a shock, the source is not the batteries. It might be the inverter if AC was not connected. .2A doesn't tell me much. What was the voltage between the driveshaft and ground?

As others have said, you need to isolate the circuits, starting with the AC side.

[skipwil]

I had a loose ground wire at the Inverter/converter. Every time I laid my hand on the awning rail it would tingle me. Tightened the set screw and all is o.k.
Hope this helps...

[Good man]

I'm with "ernieh" ...to be felt as a tingling, it is almost certainly an Alternating Current event.
But remember, it can be AC coming off the DC to AC Inverter... hence the tingling "skipwil" experienced when his inverter ground was faulty... and he involuntarily became the path of least resistance to ground.
Be aware, Motor Home Alternating Current circuits are wired with a "FLOATING NEUTRAL" as opposed to conventional residential wiring which has the neutral leg and the ground wire bonded together ONLY at the main house panel.
If this is above you, please don't be foolhardy... NOW is the time to hire a KNOWLEDGEABLE (about MH wiring specifically) electrician.
Please be SAFE with that 110/120 electrical stuff... rumor has it that it can seriously kill you. I believe it.
Take care,
Jim

[OneRVer]

I do not have an inverter so I am only asking a question. Does the inverter come off the coach batteries or chassis batteries? DFR states his chassis/engine batteries are going dead. But like skipwil states a tingle usually comes from AC. The only time that I have received a tingle is when my shore power was not grounded. Now that was a tingle.

[DFR]

Update: Finally found the time to work on the RV and try to determine the problem. When I state that I received a shock, the sensation was more like testing a 9 volt battery with your tongue than it was a AC tingle. I tested the rig today, no hookup, no generator, both coach and chassis relays off, I show .1 volts going to ground. Is this normal? Oh, I do not have an inverter.

[Gary RVRoamer]

No, its not normal. I'm guessing you have a chassis battery cable somewhere that is bare enough to touch the frame. Good hunting!

[DFR]

Thanks Gary. Would I also be correct in assuming that the short could be either between the batteries and the latching relays as well as the power cables to the relay switches?

[OneRVer]

You will have to remove each positive wire from your battery and go from there. Check from your battery to the relay and if that is good than remove the red from the output of your relay and so forth. Check for voltage at the drive line each time you have to remove a cable. Hard telling where it is coming from. Hopefully you will find it fast.

[AvoJim]

Just read the first post here. When you first measured the .2 amps ( I assume you meant volts ) were you measuring AC or DC on the multimeter? Measuring both will give you more insight into what is going on. Were your jacks down? If not, it is not clear to me how you can complete the circuit to ground. Some other part of the coach must have connection to ground, in this case the actual dirt, before your body can complete the circuit. The tires should be great insulators.
Was the shock or tingle persistent? In other words was it always there no matter how often or how frequently you touched it? And could you always measure the same voltage? If the tingle was not persistent and your jacks were not down then I have a theory. Unfortunately it does not provide an answer for your drained battery but it is possible that the tingle and dead battery are unconnected events.
It could be simple static electricy. Was it windy? It is possible that the wind produces a charge on the coach because the tires insulate it from ground and then no path to ground would be needed to discharge the static buildup into you. If this were the case you could not receive the tingle on subsequent touchings close together in time since you would have already discharged the static buildup and it would take some time to build it up again. I like this theory because

a. No AC voltage is needed to feel the tingle...static buildup can be several hundred or even thousand volts.
b. No path to ground is required.
c. I do not believe you can detect .2 volts DC with your hands. Try it on a 1.5 volt battery.
As I said this theory does nothing to explain your drained battery and I would like to know what you ultimately find on that subject. We bought our coach in April and I am in it at least once per week. I always check the battery voltage and until two weeks ago it was always good. Then one day we showed up at the coach and the chassis battery was dead. I checked all the switches and lights that I normally check when I leave the coach and everything was in its proper place. I used the house batteries to start the engine and got the chassis battery charged and have not seen the problem again. I have no idea what the cause was.
When you find out please let us know. Good luck.
Jim

[DFR]

Good theory Jim, In thinking back to that first day, I was under the coach with jacks down (to lift coach to get my large self under it) and jackstands between the frame and the cement I was parked on. It was a very humid day and I was sweating. I first felt the sensation when I was sitting in the driveshaft tunnel and leaned back. I had a burning feeling across my back from the driveshaft. Later while crawling out I reached up while laying on my back and grabbed the frame. That's when I felt it again and got out the meter. At that time I thought the short was going through the frame to ground on the battery killing the battery, and I was just jumping the current to "earth" ground. I discounted the fact that the jacks and jackstands were down. Now I'm really confused.