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Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Sat, 20 Nov 2021 3:03 +0000
by TheGruffulo
I have a 2016 SR5
Picked up a camper trailer with a Redarc 30.
It needs an active ignition trigger on Pin 2 of trailer plug to switch into using the Anderson plug from the ute.
How do you make that happen?
Do you need to bypass the ECU that is on the RHS Rear Chassis Cross Member?
I will probably end up going to an auto electrician. But I kind of want to know what I am talking about a bit before going.
Thanks.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Sun, 21 Nov 2021 10:23 +0000
by TheGruffulo
Any ideas?

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Sun, 21 Nov 2021 2:10 +0000
by dave g
I would be looking closer to the key and stay away from the ECU so you don't get any spikes that will corse hassles
Pin 2 Reversing signal or Auxiliary circuit

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Sun, 21 Nov 2021 4:28 +0000
by TheGruffulo
Thanks

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Mon, 22 Nov 2021 5:06 +0000
by Gipsy
Gruff, my uneducated guess is as follows: depending on who and how hooked up the trailer plug depends on whether the pin 2 is live or only when ignition is on. The Anderson should be a direct connection via fuse to the battery thus always live. Is it possible the 'trigger' you mention is there to switch the Anderson off when ignition is off to save your battery? It's more about the redarc and whether the power used by the accessories connected still are live when the ignition is off. If the Anderson and redarc are always live you may flatten the battery if ignition is off. The redarc should be smart enough to switch between charging and static battery voltage.
Only a guess ;)

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Mon, 22 Nov 2021 3:14 +0000
by dave g
I thought he was looking for a wire for a trigger switch. To turn on the redarc

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Mon, 22 Nov 2021 3:59 +0000
by TheGruffulo
Hi,
So the Redarc Manager 30 needs pin 2 on 7 pin flat to be active - at least 6 volts (obviously it would be 12 V +)to recognise that there is voltage coming in from the Anderson plug. It then switches to using the Anderson plug power. If it doesn't have this power in pin 2 it doesn't recognise that the power is there from the Anderson. You can change the settings in the manager to be always on. But that is not ideal. I think I need a relay to switch in power when the ignition is turned on. I'll get an auto-electrician to have a go I think. Thanks everyone.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Tue, 23 Nov 2021 5:14 +0000
by Gipsy
Gruff, my pin 2 is wired direct to the battery (my arrangement) but depending on who did the wiring it may be live always or live only with IGN on. Normally the Toyota tow harness connects pin 2 to reversing lights and you need to provide +12v via some other means and cut out the reversing lights connection. I just cut the reversing wire and added my own +12v direct via a fuse to the battery so it's always live. If this is how yours is connected, then the redarc, and thus the Anderson would be constantly live.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Tue, 23 Nov 2021 5:08 +0000
by TheGruffulo
Thanks Gipsy. That seems like a much cheaper alternative!

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Wed, 24 Nov 2021 5:30 +0000
by Gipsy
Just remember both are always live with this method, I usually unplug if I'm staying hooked up overnight so my van runs only on the house battery (deep cycle). I guess you could put a solenoid or switch in the vehicle instead of unplugging. I guess that's what the trigger means... Leaves the 12v+ disconnected when the ignition is off if pin 2 is switched by IGN?? That wouldn't be hard to arrange, just feed the pin 2 from accessories feed.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Wed, 24 Nov 2021 5:48 +0000
by TheGruffulo
Yes, I think that is where a relay would come in. That way if you pull over on the side of the road for a while and don't disconnect the car battery won't get drained.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Thu, 25 Nov 2021 3:00 +0000
by martynvella
Try downloading the manual for the redarc unit, that will explain how it works and what it needs.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Thu, 25 Nov 2021 4:53 +0000
by Gipsy
TheGruffulo wrote:Yes, I think that is where a relay would come in. That way if you pull over on the side of the road for a while and don't disconnect the car battery won't get drained.

Yes that's right, but also it depends what accessories in the camper are running at the time. A compressor fridge would be the largest load. Mine has a 12v DC fridge so it draws 15+ amps when it's running. Compressor fridges draw much less and lights are negligible for a while. You can get a gravity switch to switch off the fridge when stationary to lower the current draw when stopped. Running accessories feed to the pin2 would do that too... No IGN = no Anderson power. A simple on-off switch in the dash would also do the same, switching the 12v to the pin2. I would go for the acc feed as the simplest way.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Thu, 25 Nov 2021 7:37 +0000
by 241steve
https://www.redarc.com.au/Content/Image ... Manual.pdf
is that the box your playing with ?
pin2 on that unit controls the relay that turns off non essential loads it turns off when the battery is flat before any damage is done to the battery's.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Thu, 25 Nov 2021 9:09 +0000
by Mudgee mud
I'm a tad confused on this. As usually these are fitted on/in the vehicle. But my belief is..
From your cranking battery you will run say 6-> 8 bsa cable, (fused) .
I prefer to run twin core double insulated cable. One to positive and negative.
In your case direct to and independent Anderson plug next to your trailers 7 pin outlet. Thus your camper trailer will have two electrical hitches. One for blinkers etc, one for the redarc unit, And TOTALLY independent from each other.
And the Anderson' plug will be fed directly to redarc's positive input terminal.
( that should also have another inline fuse before your redarc + Input terminal.
negative ( 2nd core) should continue on straight to the negative pole of the campers battery negative pole.
This arrangement will only charge your camper trailer whilst on the move/ engine running.
Redarc have a diode within them, this stops any power from your camper trailer/ auxiliary battery back feeding to your cranking battery. And once you stop the vehicle/ engine off, there is no more drain from the vehicles cranking battery. Even if you tap into the original trailers continuous auxiliary power , this is not enough power to
Probably actuate the redarc unit to keep it working. As they automatically turn off within certain voltage range.
And not really recommended to drain your cranking battery out camping.
You can choose from a few different styles of 50amp rated switches for around $25 on fleabay.
# 2 position switch. P1 On/ p2 off
#3 position switch. P1 On (battery A) , p2 off, p3 (battery B)
#4 position switch. P1 On ( battery A), p2 off, p3 (Battery B) , and p4 , on both battery A+B.
* description of " battery" is the power drag supply. Thus "A" could be your cranking battery...
Using #3 means you could bypass the redarc unit via a separate Anderson plug ( fused) going direct to vans battery. Hooking up a generator, 240v ac/dc charger/ transformer/ or a solar panel.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Fri, 26 Nov 2021 2:53 +0000
by martynvella
Hey Gruff,
Best advice to you is either take it to an auto sparky or do your own research on manufacturers website not forums, and make your own decisions.
If your going to invest time and money do it on your own guesses not those off a forum.
A lot of the info in this thread is close but not close enough.
To answer your question, find an ign fuse and tap into the wire on its load side, use it to switch a relay if you wish but make sure it is spike protected.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Fri, 26 Nov 2021 2:10 +0000
by TheGruffulo
Thanks everyone. I really appreciate everyone's input on this. 241Steve, yes that is exactly the Redarc that I have in the camper trailer.

I have an Anderson plug independent of the 7 pin trailer plug. When you use the Anderson plug the manager does not register that there is any power coming in. That is because the charger "Set DC input Trigger" is set to Auto.

When the charger "Set DC input Trigger" is set to ON it allows the voltage to come in and I can charge the trailer batteries through the Anderson plug. But doing this, the current is always on and I need it to go off when I turn the ignition off. Apparently that occurs through pin 2.

Martynvella, I am going to go to a auto sparky to do it. I just really like to know a bit about it all before I go an lay down the cash.

Thanks Mudgee for your reply. I do have a decent twin core fused line coming from the cranking battery to the Anderson. Not much voltage drop which is great. The Manager 30''s installation guide on page 18 talks about the ignition trigger feature. I think that is what this is all about.

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Fri, 26 Nov 2021 2:26 +0000
by Gipsy
Good to hear you have worked it out. That's what we hope to achieve here at newhilux by 'suggesting' solutions. Martyn is correct, you do need to make your own decision but I also took your comment that you were looking for ideas as you said " I kind of want to know what I am talking about a bit before going.
Thanks."
Martyn, please don't think that we are 'experts' here, we are just a community of forum members offering help!
Free advice is just that, but just because it's free doesn't mean it's worthless ;)

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Fri, 26 Nov 2021 11:31 +0000
by Mudgee mud
martynvella wrote:Hey Gruff,
Best advice to you is either take it to an auto sparky or do your own research on manufacturers website not forums, and make your own decisions.
If your going to invest time and money do it on your own guesses not those off a forum.
A lot of the info in this thread is close but not close enough.
To answer your question, find an ign fuse and tap into the wire on its load side, use it to switch a relay if you wish but make sure it is spike protected.


You are the total demise of the concept of forums!
I suggest you log out permanently if you don't like forums members advice. Bagging members input.
Anyone can say " just take it to the auto electrician!
That's lame and pathetic information. Every person has different expectations of what they desire in this field.
I think you should just "copy and paste" take it to a mechanic, auto electrician, turbo specialists, etc!
Met your type on a few forums and don't understand why you even bother logging in.
Any foolish novice Can post what you have posted.
When it comes to newbies to forum, or long term members... 5 posts or 5000, it's about quality, not quantity.
Admin can ban me now if they see fit. But I will call a spade a spade!
But it's obvious YOU DO NOT KNOW!

Re: Need an active ignition trigger on Pin 2 of trailer plug

PostPosted: Sat, 27 Nov 2021 2:58 +0000
by martynvella
It all helps the auto sparkys. A lot of time free advice that used to come from pub talks and now forums turns a simple job into a days work for the people that actually know what they are doing.
Ive spend 40 years making money out of people like you who fish for info in the wrong places and pay people like me to fix the damage they cause because they didnt undersrand the info someone that didnt know what they were talking about gave them.
Keep up the good work pretending to know what your doing mudgee.