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dsmith · 03-04-2006, 05:17 PM

im a new airstream owner have a 22ccd 2005 and i am having some problems can someone tell me if it is normal to have a 12.75 voltage reading on one of the 7 pin trailer connection.

david

**azflycaster** · 03-04-2006, 05:33 PM

Yes and No. Look at the picture I posted in this thread: http://www.airforums.com/forum...ing-18941.html

One line (#4) is called 12 volts. On my truck that line is only active when the key is on. This line goes to the trailer battery, by controlling it with the ignition switch it keeps the trailer from draining the truck battery when you are parked.

driftwood · 03-04-2006, 05:35 PM

You are probably reading your battery in the charged state. No current flowing in. See attached for a possible lead to explain yours. On your vehicle, with engine running, the charging terminal will probably show 13.7 (+-), sometimes more.

**azflycaster** · 03-04-2006, 05:47 PM

Quote:

Originally Posted by driftwood

If it is the center pin, then it is reading your battery in the charged state. No current flowing in. See attached. On your vehicle, with engine running, it will probably show 13.7 (+-), sometimes more.

My center pin (#7) is for the backup lights and is normally 0 volts.

driftwood · 03-04-2006, 05:51 PM

There ... I fixed it!

Mike Lewis · 03-04-2006, 05:54 PM

Quote:

Originally Posted by dsmith

im a new airstream owner have a 22ccd 2005 and i am having some problems can someone tell me if it is normal to have a 12.75 voltage reading on one of the 7 pin trailer connection.

david

If you're talking about the plug connector thats on the trailer pigtail the answer is yes. One pin is connected to the battery of the trailer. When plugged to the tow vehicle this is how the trailer battery recieves it charge from the tow vehicle while traveling.------Pieman

**azflycaster** · 03-04-2006, 05:59 PM

Norm,
I just noticed your mention of the Burma Shave signs. Here in Arizona they use signs like those to warn people about the Elk. Here is one example.....

I saw an Elk

Oh what a thrill

until I smashed it
on my grill

dsmith · 03-04-2006, 06:09 PM

yes i meant the trailer plug the, reason i asked because when i turn off my car and the trailer is plugged in, the instrument panel lights in the car will not shut off and the rear wiper operates for about 1min, when i remove the plug all is well if i then re-insert the plug with the car switched off again all is well the problem only happens when i switch of the engine and leave the plug in, if i disconnect the trailer battery -all is well - therefore power must somehow be coming into the car from the battery, i checked the plug and the plug from the airstream ,one is always 12.75

thanks

david

**azflycaster** · 03-04-2006, 06:12 PM

Did you TV come with a factory installed tow package?

dsmith · 03-04-2006, 06:17 PM

yes it came with a towing package, i just dont know if i should blame the trailer or the suv.

david

lewster · 03-04-2006, 06:30 PM

David,

Sounds like you are getting some sort of feed back in your TV that is causing your 12V+ trailer recepticle power to get into other TV circuits. Does your TV have a battery isolator/serarator installed? It would also be a good idea to wire your 12V+ power lead thru a relay connected to an ignition switch controlled circuit. This will give your T/T power only when your TV ignition is switched on.

As far as blame......try the vehicle manufacturer for a start. Have them verify and tell you where and how that 12V+ gets its' power and where the connection is.

dsmith · 03-04-2006, 06:37 PM

im afraid i carnt answer your questions the airstream is a 2005 ccd 22ft so i dont know what it has i would imagine that at least it should come with the right equipment. so you are saying that it is normal to have a voltage on the trailer connector, it is on the black pos wire.

david

**azflycaster** · 03-04-2006, 06:50 PM

The black wire connects to the trailer battery and is present on my older unit. I don't know if the newer units isolate this from the TV. When I shut the engine off on my Toyota that line then isolated from the TV, most likely by a relay. If the only line you have power on is the 12 volt line (#4), I would talk to my car dealership about the problem.

dsmith · 03-04-2006, 07:10 PM

pardon mt ignorance but what is TV it is my airstream which has the plug on it which is alive and is feeding my landcruiserm the powerm if there should be power there .that is one thing if there shouldent be power there then it is the airstream

david

**azflycaster** · 03-04-2006, 07:21 PM

Sorry about that, TV is Tow Vehicle. TT is Travel Trailer. On my unit I have 12 Volts on pin 4 from the TT all the time. I have 12 Volts on the same line from the TV when the key is on. This will charge the TT's batery when I drive down the road. When I shut down my truck the connection is broken by a relay in my truck. This prevents the trailer from draining my truck's battery when parked.

dsmith · 03-04-2006, 07:32 PM

so it seems we have the same setup if the TT should have power then there must be something amiss, i can ask lexus but they are not very good at that or put in a diode? what is your advice

david

**azflycaster** · 03-04-2006, 07:35 PM

I would ask Lexus.

markdoane · 03-04-2006, 08:05 PM

I wouldn't put in a diode. You will get a significant voltage drop.

It almost sounds like you have a latching relay in the charging line to the Airstream that is keeping the circuit closed when you turn off the ignition, but opens up when you unplug the umbilical.

dsmith · 03-04-2006, 08:08 PM

what is a latching relay and were do i find it? could it be faulty?

david

markdoane · 03-04-2006, 08:39 PM

A latching relay can hold it's position after the current is turned off. These might be used because they don't require continuous application of power to keep them activated. It is also possible that the relay, if you have one, is faulty and the contacts are sticking together after you remove power. I would take it to a trailer electrician.