Posted 2011-01-29 5:59 AM (#129452) Subject: Does the Electrical System Default to Tow Vehicle?
Extreme Veteran
Posts: 489
I have had my LQ for about a year now. Used it last year and getting to know the trailer better. I have a question in regards to the batteries, if we are running the LQ on battery power and the trailer batteries empty will the trailer begin to pull power from the pickup?
In other words how do I know that I won't drain my pickup batteries without knowing? I understand I could disconnect the plug to the pickup but my concern would be that we forget to plug it in again.
Posted 2011-01-29 9:14 AM (#129460 - in reply to #129452) Subject: RE: Does the Electrical System Default to Tow Vehicle?
Expert
Posts: 5870 Location: western PA
Most trucks will not power a trailer when either the ignition is "off" or the engine is not running. This is done specifically, so that the trailer cannot deplete the towing vehicle's batteries. The truck can partially charge a trailer's batteries, but its batteries are isolated from the trailer's usage.
When the LQ's batteries are dead, they're dead until they can be recharged by the converter or more slowly by the towing vehicle.
Posted 2011-01-29 11:21 AM (#129468 - in reply to #129452) Subject: RE: Does the Electrical System Default to Tow Vehicle?
Veteran
Posts: 264 Location: Sumas Washington
With a test light you should be able to check on the trailer-truck power supply. When you find the constant hot on the truck plug when the truck is running, have someone shut the engine off. If the power stops at that time, your truck 12V is isolated from the trailer system. This is the correct way to have the truck wired. If the power stays on when the engine is off, the trailer 12v usage will drain the truck 12v system.
Does the Electrical System Default to Tow Vehicle?
