Electrical Gremlins Eating me and my Battery Alive

[sasquatchgeoff]

With so few real clues to the problem, I know it is a long shot posting for help in this regard, but I will have a go at it any way.

About three weeks after getting back from a trip, I went to plug the bargman (pigtail) into the receptacle in the bed of the truck, and when I did, I heard a small 'pop' and then actually saw a little plume of smoke rising up from the barman plug/socket. Instinctively, I knew this meant trouble, but tested everything, including signal/stop lights and compartment 12V functions and it seemed to be normal. When on shore power, battery charges, everything works - except the backup lights.

However, after time I discovered (and this is the problem) that the only battery in my rig was not-so-slowly discharging at the rate of about one day and its dead. When boondocking I have to break out my generator and plug into AC 3 or 4 hours before bedtime to have a furnace to run all night. Its still pretty cold in the hills here.

I bought a new battery because the old one would not take a charge any more. This gremlin may have killed it, or maybe it was its time. I'll never know. With a new battery, I still had the dead-in-a-day issue.

So today, after determining that I indeed had a dead short somewhere in the camper, I broke out my trusty multimeter. Here is what I get when I test the power and ground at the Magnatek, as well as one each of the red and white 12V leads that attach to the battery terminals in the battery box. Apparently there is a short, since the conductivity registers, but shows a resistant connection when it should be, based on my extremely limited knowledge, no connection between the main positive and negative terminals.



Now, I get this same 1/3 of a dial worth of resistance on the ohmmeter when testing the backup light pin (neg) and power pin (pos) on the bargman plug. Remember the backup lights no longer work.



I bought a new bargman plug and will install tomorrow before heading out on a trip to Central OR where in the hills, the night time temps can get down to the teens.

Any ideas, or suggestions, or even insults are entirely welcome.

[sasquatchgeoff]

UPDATE: I did exploratory surgery on the pigtail, as mentioned in my last post.

Found out when I replaced the bargman plug, the red (right turn/stop) wire was joined by a cheezey crimp-style butt connector. Since I didn't have a right hand turn or stop, I went back in, removed my beautiful shrink wrap, soldered/lugged the red wire (no crimp connectors for me) and heat-shrink wrapped it back up.

Now there is no drain to the TC battery as before. Any of the stupid crimp-style butt connectors could have been the culprit (I cut all but one) or it may have been two of the badly-oxidized wires under all those miles of cheap electric tape that were only mildly shorting, but enough to cause a drain.

I cut off approx 4 feet of homemade extension, back to the rubber of the original pigtail, and all appears to be well.

Spent three nights boondocking in Central OR over the weekend, and with a family of four, dishes, furnace clicking on and off all night long, lights, CD player, jacks (first night) etc, I was getting about one day for each charge from my genset, which is livable.

Solar (at least 200 watts) is on my horizon...

[Joe417]

It sounds like you are talking about the TC battery and not the truck battery. On the average unmodified TC, your running lights, tail lights, backup lights, and turn signals don't connect to the TC battery. They operate from the truck electrical.

One thought, the furnace blower pulls quite a bit of current. I don't have a problem with an overnight furnace run but I have 2 group 29's. How much current do you have available?

The only normal thing I can think of that would run the battery down quickly is if you had a 3 way frig and it was running from 12V. Most are around 300 watts.

But, since you removed the fuses and still ran the battery down, there has to be a path to ground that isn't a dead short.

I think I would check the output connection of the converter. There are filter caps in the output of most converters that could be very leaky and drain the battery without causing a dead short. The converter would still operate when connected to AC power, charging the battery, although the DC output would be noisy.

To verify, depending on the converter, you should be able to pull the fuses on the converter output or disconnect the wires that run from the converter to the fuse box.

I have seen a few flakey Magnatek converters.

Good Luck,

[YC_1]

If you have no way of measuring the current draw you cannot assume it is that killing your battery. Often when a sick battery exhibits symptoms of a quick run down it is just having problems internally and any small draw can make them act really strange. A load test and hydrometer will tell the tale in a couple of minutes.

Keep in mind that we do not BUY batteries, we rent them. Even new ones can be bad. So my suggestion is to NOT keep fixing wires and plugs until you have solid concrete information. If you poke around trying to fix the issue I can almost guarantee you will install more problems.

A healthy battery should not run down in a matter of hours. If it does you will have something hot or melting or worse.

It can be confusing and distracting with fuses blow etc but I think it is time to get back to the real problem now.

Ok, off my soap box. Have fun.

[sasquatchgeoff]

copeland343 wrote:
Did you connect the battery backwards when you replaced it last week?

Red to positive, white to negative right?

But when changing the bargman pigtail plug, it had the white and black swapped. I left it like it was.

Changing the bargman plug did not fix it. Replaced all the tail lamps too.

The pot of gold at the end of the crappy rainbow is the backup lights work now. The battery is still draining though.

The PO created a monstrous extension to what was probably once a nice bargman pigtail. It had several of the plastic barrel crimp unions and more cheap black electrical tape than I have ever seen in one place. My hands were covered in black goo.

Gonna replace the entire pigtai next.

[copeland343]

Did you connect the battery backwards when you replaced it last week?

[HMS_Beagle]

I would check inside the pigtail shell. The contacts in many of those are very close together and may be touching in the shell.

I had a backup light issue, would blow the fuse on the camper running lights in the truck. It was an intermittent short buried somewhere in the left rear corner of the camper beyond accessibility. It took me a year to find, I eventually had to wire around it.

For debugging this kind of short, the very best tool is a sensitive DC clamp ammeter, will cost you about $80. You can clamp it on any wire and it will tell you how much current is flowing through. That lets you quickly determine which circuit is at fault, and trace through the circuit to localize it.

[WyoTraveler]

Previous posts are correct. Test light is the way to test. I would also check the socket with TC unplugged. Make sure you have voltage on the proper pins coming from your PU. If backup lights work on your PU (without TC plugged in) and don't work on the TC when plugged in you are probably correct the problem could be in the plug or socket or wiring to the socket. Keep in mind a loose wire can also be a problem. My concern is about the popping sound when you plugged it in. Assuming your ignition is off and PU lights are off when plugging in seems like there shouldn't be any voltage on those pins, except from the TC battery unless there is a loose or shorted wire in the plug or socket.

Make sure when using your test light pick up your ground at the pin on the plug first. If you then see a problem of no voltage on a pin move to a chassis ground for your ground. A bad ground can be easily overlooked. Doesn't matter which ground you pick up first. Just be aware a loose or missing ground on the plug or socket can be easily overlooked.

[zcookiemonstar]

Maybe you need to double check how you connected the battery.

[sasquatchgeoff]

I probably should have mentioned that I installed a brand new battery last week. I agree it is not a severe short - else I would be smelling smoke or stuff would not be working at all.

Another thing I did prior to this latest round of testing today, was removing all 12V fuses in the panel only to come back a day later to find that the battery was drawn down considerably after a complete charge. From that I concluded that the problem was not in the individual circuits in the camper compartment, and that it likely was either in the path on the way to the panel, or an external connection - which would be the pigtail.

I will get a test light - been needing to do that for a while. Thanks for the suggestions - I think I'm closer now.

[YC_1]

Using an ohmeter may just drive you crazy. You have a built in signal tracing component. Your truck batter.

Start by checking the outlet on the truck with a test light versus a voltmeter. A voltmeter can fool you however your analog meter is less likely to.

Check that all functions are good. If you find the backup light function missing then find the fuse that popped. It is easy to turn one of those plugs over just enough to pop a fuse.

With that sorted out you can move on to the battery that is probably sick. If you have a severe short things will melt and fuses will blow. I doubt you have a severe short. You can lift the battery lead off the camper, with the things not plugged into shoreline or the truck, and put your test light in series with the cable. If it lights, you have a decent draw and then need to chase that.

Simply pull each fuse in the panel to isolate the circuit that is shorted if your find the test light is glowing.

[sasquatchgeoff]

zcookiemonstar wrote:
as dumb as is may sound try removing the bulbs from your reverse lights and see if your problem goes away. I have had bad bulbs cause problems with low voltage controls.

I thought of that after I posted. First thing on my list to check tomorrow...

[zcookiemonstar]

as dumb as is may sound try removing the bulbs from your reverse lights and see if your problem goes away. I have had bad bulbs cause problems with low voltage controls.