If you don't unhook, what about electrical?

[patodonn]

What are the "pros and cons" on leaving the "umbilical" from the truck to the RV connected (or not) if you decide to leave the rig hooked up overnight?

We disconnect, even if we leave the truck hitched. No real reason, just the way we've always done it.

Does it make any difference if you happen to be in a CG with power and still don't unhitch the truck?

Thanks,

[JH Sechelt]

Hi JP,

Most charging systems to the trailer are on & off with the key, or in some cases run off a second battery in the truck .
( a none starter battery ) One could check that with a test light on the plug of the truck to be sure.
I leave the trailer plugged into the truck if we are only stopping for a night and not disconnecting the truck.
I doubt that we would every stop anyplace for more then one night, and not disconnect the truck for day use, like over 2 or more days.

J&D

[lawrenceb42106]

I always disconnect the trailer plug when staying overnight. Just a habit I have always done. May have a fluke problem and get a feedback to the truck.

[stiles watson]

I don't think it is a good idea to have the shore line and truck hooked at the same time. If I remain hitched but connected to the CG power, I always disconnect the truck electrically.

[Glenn and Lorraine]

I leave the truck electrical hooked up while connected to a shoreline if we are just overnighting. Right or wrong I have never had a problem.

[padredw]

Once again I find myself in agreement with Glenn. Maybe we have just been lucky? If so, I have had a long string of good luck. It will soon be five full years and nearing 50,000 miles in our Montana and Chevrolet pickup. We often remain connected for overnight stops.

[Mudchief]

If I hook up to ac I leave the truck connected. If not I unplug the truck so if something should short or start pulling a heavy load It won't run the truck batteries down. On my truck there is 12 volts going to the unit even with the key off.

[Bill and Ann]

Same here Dennis. The terminal to the trailer from the truck is live with the key on or off.

[H. John Kohl]

I thought pin 4 on the trailer hookup was relay switched on the Tow Vehicle by the ignition. I pulled out the trusty volt meter and find there is 12 VDC there all the time on my TV. So with that knowledge, I recommend unplugging from the TV. This is more critical if your running your furnace or lots of 12VDC appliances. The fan motor for the furnace draws a lot of current.
Good luck and tow safe.
Cheers,

[VanMan]

I disconnect (habit ??). And when I hookup I have the truck running when I connect just in case the RV battery is dead (or low) and the two try to even out - I'm not even sure that's possible but I think I read it somewhere.

[richfaa]

We have always unplugged .Got that advise from a fellow Rv'er many years ago. Note the in the case of our meltdown it was the charge line that melted and if we had been plugged into the truck would have caused serious damage to the truck..so you never know and because it has never happened before(never had to us) does not mean it will not happen ..ever.

[patodonn]

So, in summary, looks like the consensus is to unplug the truck electrical if you are remaining hitched to the truck for an overnight stop, with or without AC power available for the RV.

Kind of what I thought, but wanted to get some highly experienced and wiser folks opinions/reasons. Makes sense that if you aren't plugged in, mysterious and unexpected bad electrical things can't happen through that connection.

Now, I need to develop a "foolproof" way to remember to connect the next morning before heading down the road. Thought I had one, but it didn't work one morning last Nov when I was by myself, heading West. Figured it out about 100 yards down the Interstate, 1/2 mile from the CG. Reason was (1) Almost never remain hitched overnight because we take two nights at each stop, and (2) Almost never travel by myself. Broke my habit pattern(s), big time, and that was the result. Hopefully, we (all of us)learn from individual mistakes. Be careful out there!!

Appreciate all the inputs...best to ya' all,

[Cat320]

I unplug, too. Don't trust that electical stuff, never know which way current is flowing. As for remembering to hook back up in the morning, on my Prodigy, when the Montana is not plugged in I get two dots with a blank space in the middle of the display window. When hooked up a big "C" is in the middle of the two dots in the display window. I think of the C as "connected."

[bsmeaton]

When redoing my wiring for the new truck (06 F350), I noticed my charge lines shuts off with the ignition. My old Ford did not.

I always unplugged as a rule for fear that the Monty would drag down the batteries in the truck if I was not plugged into AC, and if I was plugged into AC, I was concerned that the converter may try to charge my truck batteries through the alternator connection.

I guess with the new truck, it makes no difference.

[genecurp]

Patodonn,
A fool proof way to remember to re-plug the trailer to the truck is to review your Hitch Up Checklist. You will have many things you will get to skip (lower tailgate, back to within a foot of the king pin, etc). But the checklist would include the umbilical cord, raising up the rear stabilizers, raising front jack landing gear, testing the lights, checking air pressure and other important
stuff you want to check before rolling every day. Even unplugging from shore power.

Thank goodness for checklists.
Gene

[Connorsmom]

Yea,
Even though I don't unhook, I always unplug the umbilical cord. When I drove semi over the road, it was common practice to ALWAYS check your fifth wheel pin and air lines anytime you left the unit for any length of time. There are people out there who think it's funny to switch air lines on you, unhook them altogether, or even pull your fifth wheel pin. So, I've found I'm still in the habit of checking the fifth wheel pin anytime I leave my truck for any reason, which would include in the morning before pulling out. I automatically see the umbilical cord umplugged, so that parts easy. I've been looking for something to put into the hole on the pin latch so it can't come undone unless I'm the one undoing it. I just hate having to deal with yet another lock and key. I was thinking about some other type of latch. I'll just keep looking...

Jan

[bsmeaton]

Jan,

I went to Ace hardware and bought a 4-padlock set all keyed the same with brass keyways. I have the key on all the Monty keychains and use the locks for the hitch, wheel chock thingies (I don't use anymore), the inside safe (2003 model), pin stabilizer, or anything else I happen to think of. I just keep the spare locks in the basement when I'm not using them.

[Connorsmom]

Brad,
Now THATS a great idea!! I have two corners of the hitch padlocked with matching keys, having them all keyed the same would really help alot. Thanks for the idea...
Jan

[Bighorn]

Try installing an isolator like the one offered by Hellroaring Tech Hellroaring Technologies http://www.hellroaring.com/
Be careful if you use a diode type isolators it will cause a 0.7 volt drop in the system. The hellroaring isolator will have less than 0.005 volt loss. The Hellroaring isolator prevents the 5er battery from discharging the truck battery until the alternator is putting out.

The following site may help answer any question related to this issue.
http://bart.ccis.com/home/mnemeth/12volt/12volt.htm

Ed

[dsprik]

On the rare occasion when we are staying at a Wally World or a Cracker Barrel, I unhook, pull around to the back of the Montana, and plug in the Kipor 3000ti. It's quiet, especially sitting down inside the bed, up against the passenger side cab. Gen is cable locked into the bed. Don't have my 3000 watt Coleman converter yet, so this is the way we boondock.

Info that I have picked up over the past year and a half on this forum has me "reflex trained" that if the truck ain't runnin', that umbilical is unplugged immediately...