Brake Controller - Inactive current draw?

[chuyler1]

I wired my controller up as per eTrailer.com's instructions as well as the instructions that came with it. I used an auto reset circuit breaker for the power lead. Unlike a car radio though, there is no accessory power cable so it appears the unit stays on all the time. Is that normal? Do you unplug the unit when not in use? Why wouldn't they just supply a power on/off switch with the unit? I'm afraid of killing the battery when I don't drive the truck for days.

[Ron in BC]

Mine is hooked up fulltime but there is a wire that goes to the brake light switch. The controller only receives power when the brake pedel is depressed enough to activate the brake lights so there isn't any power drain with it hooked up continually.

[Byron Kinnaman]

Originally Posted by chuyler1

I wired my controller up as per eTrailer.com's instructions as well as the instructions that came with it. I used an auto reset circuit breaker for the power lead. Unlike a car radio though, there is no accessory power cable so it appears the unit stays on all the time. Is that normal? Do you unplug the unit when not in use? Why wouldn't they just supply a power on/off switch with the unit? I'm afraid of killing the battery when I don't drive the truck for days.

If it's prodigy it'll turn itself off and turn back on when the brake pedal is pressed.

[Carol H]

Mines a prodigy & the digital display comes on when the car is stared showing if there is a connection or not. It goes to sleep a short time after the car is shut off.

[chuyler1]

I got the Prodigy P2. I guess I'll leave it plugged in for a while and see if it turns off. I left it for a few minutes and two of the LEDs were still on.

[hillary]

I have the P2 as well and was worried about this when I first got it but haven't had any battery issues and have noticed the blue glow goes away after the car is off for a bit. It's been installed for a couple months now, and we've gone at least 4 days without driving a couple times. The odd thing to me is that sometimes it knows it's not connected to anything immediately and other times it starts out thinking it is and showing numbers only to realize n/c 30 seconds later!

[Brian B-P]

Originally Posted by chuyler1

Unlike a car radio though, there is no accessory power cable so it appears the unit stays on all the time. Is that normal?

Yes, that's normal. It stays on, but as others have explained it is in a sleeping mode, using very little power, like most modern electronic equipment.

Originally Posted by chuyler1

Do you unplug the unit when not in use?

I unplug and remove my Prodigy when not in use - although not necessarily at every stop on a trip with the trailer - more to get it out of the way than for any power consideration.

Originally Posted by chuyler1

Why wouldn't they just supply a power on/off switch with the unit?

My guess is that they are concerned that people would forget to turn it on... and that the sleeping power draw is too low for a switch to be needed.

Originally Posted by chuyler1

I'm afraid of killing the battery when I don't drive the truck for days.

There are likely other components of the truck which do the same thing; even the radio which won't play without accessory power is likely connected to power that is always on so it can keep its memory alive. My guess - and again this is only a guess - is that days are not a problem, although weeks might be a concern.

[frank_a]

That's what I did, was hook it up so it could easily be removed. Once we get someplace to camp, if I'm running around, I simply un-hook it.

Frank

[Carol H]

Mine has been plugged in for 6 years - no issues with battery drain on the car. It uses very little if any power once asleep

[chuyler1]

Alrighty, thanks guys! Sounds like I have my answer. I'll leave it plugged in most of the summer but I will probably unplug it over the winter when the vehicle often sits for a month or two without being driven.

[Byron Kinnaman]

Originally Posted by Carol H

Mine has been plugged in for 6 years - no issues with battery drain on the car. It uses very little if any power once asleep

Me too. I just leave it there in it's little bracket plugged in. Removing it or unplugging is just one more thing to forget to put back in or plug in.

[MCDenny]

Regarding phantom loads, like the radio, the big one is if you have a keyless entry system where you can leave the key fob in your pocket and the car detects it via an RF inquiry signal. The car uses power to check for the key all the time. Our Prius has a small I think 34 ah 12v battery and it will be dead if it sits for a month. It, and probably all cars, have a switch to turn off the keyless feature if you are not using the car for an extended period. A regular car would have at least twice as big a 12v battery but the same process would drain it too.