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wildwoodrver · 10-29-2005, 06:47 PM

After a 3 night dry camping trip, we departed for home with very low batteries (as expected). The problem was that after 3 hours of driving (and a wee bit of help from the 55 watt solar panel) we still had very low batteries when we arrived. I don't think the batteries are charging off the TV.
Any help on trouble shooting?

john hd · 10-29-2005, 06:55 PM

wildwood

lets start with the basics, what kind of trailer do you have?

do you have 12 volts at the trailer recepticle on your tow vehicle?

john

overlander63 · 10-29-2005, 07:01 PM

Yes.
First, check to make sure the charge line from the tow vehicle has power. If you aren't getting power through the plug, it can't get to the trailer. All you should have to do is use a test light, and make sure it lights when you touch the lug for the charge line in the tow vehicle plug. If you have power there, the next thing to check is if it is getting to the battery. Using the same test light, touch the corresponding lug in the trailer plug, and make sure the test light lights. If it does, chances are the charge line is doing all it can to charge the trailer battery.
The best way to describe this, is to equate your battery to a milk jug. The milk jug (battery) holds, for example, 500 amps, and it is almost empty. Now you are going to fill this jug with a straw (charge line) capable of putting 10 amps per hour in the jug. It will take 50 hours to fill the jug at that rate.

CanoeStream · 10-29-2005, 07:16 PM

Hi wildwoodrver -- Welcome to the Forums. Why don't you fill in your personal data so we can at least see if you have a newer or vintage AS?

How far was the drive from your camping area back to home? Terry points out the same issue I will address -- your tow vehicle's alternator is built only a bit larger than the charging demands for its own battery. Terry's example suggests that it takes a goodly trip to recharge a significantly discharged battery. Lead-acid batteries get worn out if discharged to less than 30-40% with regularity. A continuity tester is a fair start but it is most useful to get a VOM multimeter. ... ... uhh, try the Search function, keyword 'Sperry' is just a thought.

wingfoot321 · 10-29-2005, 07:24 PM

wildwoodrver,

What year and model of tow vehicle do you have. My 2003 GMC did not have a fuse in the fuse panel for charging the trailer. Even though I paid for a tow package on my new truck, they forgot to install the fuse. You have to look close because they put in a dummy plug in place of the fuse?

Bob Thompson · 10-29-2005, 08:01 PM

Another consideration, are the trailer batteries low on electrolyte or are they at the end of their useful life?

wildwoodrver · 10-29-2005, 08:42 PM

Thanks for quick response to a vague question!
The AS is a 2005 CCD. It turns 1 yr old next week. TV is a 2005 GMC Yukon XL. I watch the battery water like a hawk. It is fine. Batteries should be fine. To get more specific, which pin in the 7-way plug carries the charging current? I can test it with a multi meter. If that is ok, any hints on where I can trace it to? I've been under the couch to hook up the solar panel....I should find a charging wire there, no?

Thanks for your help.

john hd · 10-29-2005, 08:52 PM

"which pin in the 7-way plug carries the charging current?"

easy!

look on the cover of the recepticle, it has a diagram showing what is what.

look for the +12 pin.

john

**azflycaster** · 10-29-2005, 08:57 PM

These pictures show the pins of the connector and what they do. The power line to the trailer is pin 4.
The left one is the car end of the cable and the right one is the trailer end.

john hd · 10-29-2005, 09:00 PM

az,

the center pin on your diagram should be backup lights.

john

SilverRanger · 10-29-2005, 09:03 PM

If I recall, the owner's manual for my 05 Bambi has a wiring diagram for the plug. Did you check there? I noticed you said you have a 55 watt solar charger. Same here, but mine came with those maintenance free glass mat batteries and they work great so far. The lowest they have been discharged is down to about 70% after a night of using the lights, CD/radio, and reefer (on gas), but the solar panel charged them back to 100% in about 4-5 hours of sunlight the next day.

**azflycaster** · 10-29-2005, 09:06 PM

Quote:

Originally Posted by john hd

az,

the center pin on your diagram should be backup lights.

john

I would rather move ahead. Did you ever notice that bad things happen mostly while in reverse?
Thanks for the corection!

cammur · 10-29-2005, 10:02 PM

Thanks for the great picture, az (with John's additon). I've printed it for my "collection". I wish the Airstream manual were as clear.

Cam

Pick · 10-30-2005, 06:34 AM

3 hours might not have been enough to charge the battery if it was really low, as your charging current is limited. Plug into shore power for 24 hours and see how the battery condition is after a good charge.

cammur · 10-30-2005, 11:08 AM

Az,

The original poster has a 2005 CCD and I have a 2005 Safari.

I'm wondering if the 7-pin assignments might differ over the years. At least, when I compare your nice diagram with the not-so-nice diagram in my manual, wire color and assignment differ greatly.

Any thoughts as to what is going on?

CanoeStream · 10-30-2005, 11:33 AM

Hello Cammur -- Airstream's entire FAQ page is valuable. Please see http://www.airstream.com/product_lin...ervice/faq.tea and click on 'Plugs.' You'll see the functions are just as azflycaster's diagram suggests. I've seen the colored diagram in this thread before and don't believe it's from an Airstream source. My 2006 manual doesn't seem to have an umbilical wiring diagram in either the towing or electrical sections...

Though the Airstream website says "to 2002" it really means "to present" and would pertain to the trailers mentioned. This is how you need to match your plug to current day tow vehicle setups regardless of wire color. When rewiring my Argosy there was some variability in wire colors but it was pretty easy if I just paid attention to function.

72 tradewind · 10-30-2005, 11:41 AM

put a voltmeter on your coach battery and start your tow vechicle. you should see an increase of about 1.5 volts. i.e. 12.0v before you start it and 13.5v+ after. you should have a fuse in your coach on the vehicle charge line, check your owners manual.

markdoane · 10-30-2005, 11:44 AM

The plugs on the airstream site don't match the universal plug color diagram in Azflycaster's diagram.

The colors are different, which doesn't make any difference as those wires are all the same size, 14 gauge.

Most umbilical cable comes with 2-10ga wires (12V+ and ground), a single 12ga (brakes), and 4-14 ga wires for the lights.

As long as you keep the 10 ga and 12 ga wires coded properly, the other wires can be whatever color you want, as long as you write it down.

I prefer to stick with what 99% of the world uses, which is the diagram in Az's post.

cammur · 10-30-2005, 02:38 PM

Agree, diagram in FAQ (see Canoe post) matches diagram in AS manual for my 2005, color and purpose. Diagram also matches Az's post in terms of purpose for each terminal, but not in terms of wire color; note this holds true as long as what Az calls the "car end" is actually the "trailer end".

That was certainly a confusing sentence I just wrote - hopefully my meaning is clearer.