Electrical 12 Pin plug query

darcy305

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Jul 24, 2011
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Hi all,
Just a quick question regarding the 12 pin plug. Does the the van battery get charged via pin # 9 or pin# 2?? or is pin #2 just to get power into the van to runs lights etc if there is no battery we have a 2015 17.56.1

Tia

Danny
 

mikerezny

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Hi all,
Just a quick question regarding the 12 pin plug. Does the the van battery get charged via pin # 9 or pin# 2?? or is pin #2 just to get power into the van to runs lights etc if there is no battery we have a 2015 17.56.1

Tia

Danny
Hi @darcy305,
in normal Jayco wiring, the tug should have 12V wired to pin 2. On the van, pin 2 goes to the AUX External input on the Setec power supply and battery charger.

If the battery switch in the van is in the on position the tug will charge the battery in the van via a diode in the Setec unit. So there is a 0.6 ~ 0.7 V drop.

If the battery switch is in the off position, the van battery will only be trickle charged at 0.8A.

If you don't have a van battery, then 12V on the AUX input (pin 2) will also power the lights etc.

This is all explained in the Setec manual. If you don't have a copy, it is available at:

http://www.setec.com.au/wp-content/uploads/2013/07/023942-ST-III-User-Manual-D.pdf
http://www.setec.com.au/wp-content/uploads/2013/07/023942-ST-III-User-Manual-D.pdf
There are a lot of threads on this forum relating to wiring up your tug correctly to run the van and, in particular, the fridge
and explaining the 12 V setup, especially relating to adding solar panels.

I hope this helps.

kindest regards
Mike
 

achjimmy

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Jan 24, 2011
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@mikerezny thanks. So the esc runs of pin 2 as well? (Which is reverse lights in Toyota wiring )

Is the above why even if the battery switch is off you sometimes notice a light on in the van when towing? 12v is still getting through?

I was planing on moving my Jayco heavier pin 2 wire to pin 9 as this will be a switched power source on our tug. I want the ability to switch off esc occasionally
 

mikerezny

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@mikerezny thanks. So the esc runs of pin 2 as well? (Which is reverse lights in Toyota wiring )

Is the above why even if the battery switch is off you sometimes notice a light on in the van when towing? 12v is still getting through?

I was planing on moving my Jayco heavier pin 2 wire to pin 9 as this will be a switched power source on our tug. I want the ability to switch off esc occasionally

Hi @achjimmy,
pin 2 has a dual purpose. It can be used either for reversing lights OR as +12V. Jayco use pin 2 as +12V. The Jayco document, JAY-12PIN-F1 issue 1, 03/03/14, supplied when we bought our Penguin last year, Step 2 details, removing the existing reversing wire and taping it back, then wiring 3.0 mm2 directly to the tug battery via a 20A fuse.

I assume, by noticing a light on in the van when towing, you mean a green light on the Setec panel? The orange one will be on if the battery switch is on. Good question, I have never looked. Something for me to check next time I am towing.

I don't have ESC so I can't comment.

cheers
Mike
 
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ChrisFatboySydney

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Feb 29, 2016
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Hi all,
Just a quick question regarding the 12 pin plug. Does the the van battery get charged via pin # 9 or pin# 2?? or is pin #2 just to get power into the van to runs lights etc if there is no battery we have a 2015 17.56.1

Yes, pin 2 powers the ESC if fitted.

Ck
 

achjimmy

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Jan 24, 2011
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Hi @achjimmy,
pin 2 has a dual purpose. It can be used either for reversing lights OR as +12V. Jayco use pin 2 as +12V. The Jayco document, JAY-12PIN-F1 issue 1, 03/03/14, supplied when we bought our Penguin last year, Step 2 details, removing the existing reversing wire and taping it back, then wiring 3.0 mm2 directly to the tug battery via a 20A fuse.

I assume, by noticing a light on in the van when towing, you mean a green light on the Setec panel? The orange one will be on if the battery switch is on. Good question, I have never looked. Something for me to check next time I am towing.

I don't have ESC so I can't comment.

cheers
Mike


Thanks mike. I have actually stoped and had the van interior lights on even though I had the main off!! Jayco have no idea so presuming it's around that trickle charge you mention?
 

mikerezny

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Thanks mike. I have actually stoped and had the van interior lights on even though I had the main off!! Jayco have no idea so presuming it's around that trickle charge you mention?
Hi @achjimmy,

ok, no I understand. Yes, if you have 12V on pin 2 which goes to the AUX external input of the Setec, then this will supply 12V to the van lights, etc regardless of whether the battery switch is on or off.

If you also have a van battery, it will be: 1: trickle charged from your tug at 0.8A if the battery switch is off or 2: charged if the battery switch is on.

cheers
Mike
 

achjimmy

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Jan 24, 2011
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Hi @achjimmy,

ok, no I understand. Yes, if you have 12V on pin 2 which goes to the AUX external input of the Setec, then this will supply 12V to the van lights, etc regardless of whether the battery switch is on or off.

If you also have a van battery, it will be: 1: trickle charged from your tug at 0.8A if the battery switch is off or 2: charged if the battery switch is on.

cheers
Mike

Thanks mike. I can now inform the experts at Jayco who we intrust to service and fix our vans of what the issue is and not to worry :D
 

MDS69

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Jul 6, 2014
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In the OB models I thought the battery was charged via the solar panel in all situations ie parked up on the driveway at home, set up at camp or under tow on the road.
 

mikerezny

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In the OB models I thought the battery was charged via the solar panel in all situations ie parked up on the driveway at home, set up at camp or under tow on the road.
Hi @MDS69,
this is my understanding:

In a 'typical' setup, the solar system is wired via the solar controller directly to the battery. So if there is sunlight, the battery will be being charged. The solar setup is completely independent of the Setec power supply and battery charger. 12V from the tug and 240V go into the Setec to supply the van's 12V requirements and to also charge or trickle charge the battery.

So, in effect, if the solar panels are working, the van battery may be charged from two sources: via the Setec from tug 12V or 240V and via the solar panels.

kindest regards
Mike
 

Dobbie

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Jun 18, 2014
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Agree.

We've found the onboard solar to be far more efficient in charging than the connection via the vehicle. It's really just a trickle charge to keep the fridge ticking over.
 

Dean Anderson

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My dealer said pin 2 is normally for the ESC and charging the breakaway battery with Jayco. I have him connecting it to pin 9 instead so I can put reversing lights on the van without changing the car wiring away from the standard format.

upload_2017-3-21_16-23-38.png

The above normal wiring positioning is from Narva.

I don't think the tug charges the van battery at all on new Jayco vans unless you have done it as an extra (usually via an Anderson Plug and additional wires to the supplied loom).

I was told Jayco does use a 10mm wire for the large fridge in the new vans which looking at the size standards is likely 9mmAuto or 8B&S. I used 6B&S on the present van and found it fantastic, so I have my doubts about 8B&S being big enough to stop enough voltage drop considering the size of the fridge.
 
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achjimmy

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My dealer said pin 2 is normally for the ESC and charging the breakaway battery with Jayco. I have him connecting it to pin 9 instead so I can put reversing lights on the van without changing the car wiring away from the standard format.

View attachment 48483
The above normal wiring positioning is from Narva.

I don't think the tug charges the van battery at all on new Jayco vans unless you have done it as an extra (usually via an Anderson Plug and additional wires to the supplied loom).

I was told Jayco does use a 10mm wire for the large fridge in the new vans which looking at the size standards is likely 9mmAuto or 8B&S. I used 6B&S on the present van and found it fantastic, so I have my doubts about 8B&S being big enough to stop enough voltage drop considering the size of the fridge.


I found the heavier wire Jayco used for the thetford adequate for its performance. Just the 12 pin plug couldn't keep up.
 

mikerezny

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I don't think the tug charges the van battery at all on new Jayco vans unless you have done it as an extra (usually via an Anderson Plug and additional wires to the supplied loom).
Hi @Dean Anderson,
interesting...

I will now have to check the wiring next time I am towing. I have a late 2016 Penguin, so I will class that as a new van.

My understanding is that 12V supplied on pin 2 will go to the EXT / AUX input of the Setec unit. If this is so, then when connected to the tug, it will supply 12V to the van for lights etc, irrespective of whether the van has a battery or not.
If the van has a battery, then, according to the Setec manual, it will be trickle charged if the battery switch is on or charged if the battery switch is off.

It is easy to check. I have +12V wired to pin 2 on my tug as per the Jayco instalation guide I was given when I signed the contract.
So, when I next connect up, I will switch the van battery off and check if the exterior annex light is still working.

cheers
Mike
 
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mikerezny

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I found the heavier wire Jayco used for the thetford adequate for its performance. Just the 12 pin plug couldn't keep up.
Hi @achjimmy,
I am not at all sure it is the plug or the connection from the van cable to the plug.

When I bought our van a little over three months ago, I checked the screws on both the 12-pin plug and socket to make sure they were tight.

Last week, out of curiosity, I checked the plug again and the 2 screws for the heavy-duty connection to the fridge were barely done up. Luckily, I could see no damage caused by heating. So I am going to check this every three months from now on. If it happens again, in goes the Anderson plugs.

Further, I now check the plug each time I disconnect and feel if any of the pins are hot.

I have a small voltmeter permanently across the fridge and my Prodigy brake controller will tell me the battery voltage in the tug.
Each time we hook up, as part of testing the lights, we check the two voltages. There is usually have 0.7-0.8V difference in voltage.
If there is no difference, then the fridge is not working on 12V. Better to find that out before we leave. If there is more than 0.8V I have an abnormal voltage drop that I need to investigate.

Sounds like overkill, but in reality, it takes only an extra 10s to read the voltage supplying the fridge when we connect. And only a couple of seconds to feel the temperature of the pins on the 12-pin plug when we disconnect.

cheers
Mike
 

achjimmy

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Mike you could be right about it coming loose! It worked well for 12 months till it got hot then the split pin wouldn't stay open and that was it constantly hot after that. Iam just not that conscious to check all the time and my tug is already wired with twin andersons through a relay for a fridge

Over the years I have seen so many instances of no lights etc cause the fridge has caused an issue. Was just easier to run 6m of 6b&s and be done.
 

Dean Anderson

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I probably go a bit overboard with my wiring...the way I see it the extra few dollar for me is an extra few dollars....for Jayco...times it by every van produced and somebody has the job to minimise costs, or they don't have a job.

I've got a 175Amp Anderson on my car with 3B&S to the back of the car via a VSR, picking up earth at the back from the chassis and body. Just a personal thing I suppose, I hate large Amps going through little connectors and little wires even though they should theoretically be able to handle the load..

Looking at fuse wires really gets me....100 Amp through something that size???....suppose it has to pop some how...

Poor connectors is a major problem...I've melted a few cig plugs to fridges the last year because they wobble a bit loose, going to all Anderson plugs now... ...It's always good to eliminate possible problems.

I luv stuffing every opening with as much copper as possible....Then I know it ain't the cable size to blame...All I could get from the front to back of my car was 3B&S without running cables outside the entire length of the chassis.

And don't underestimate a good joint.....They make you feel real relaxed.....

Use a proper crimping tool......Solder all lugs (>10B&S)....Use double wall heat shrink.......

Over engineering with electrics, I believe is the way to go........
 

Drover

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While I used to think the 12 pin was okay to run the fridge, I changed my mind when it melted down and for those who are serious about having decent cabling, well if you are then you wouldn't use the 12 pin as the heavier cable doesn't fit unless you pair it down a bit, use an Anderson plug then it's do it once and forget about it.
Jayco wiring is usually shambolic, 12v power from tug will go to a birds nest of connections usually under the van where it will split in a mangled join to run to the fridge and the Setec, this always needs attention and makes any other upgrades a waste....(unless you already have an Anderson wired in but I would still have a look at the birds nest and check how/where they wired the anderson up sometimes it's a bit iffy )............power for the breakaway and ESC should have no other connections to it and are supposed to run independant to whatever you do in the van but have seen the Breakaway power piggy backed off something else on the 12 pin, so always check.....
If you have solar don't waste your time doing anything about the tug charging your battery.....the panel does a far better job.
Only use cig plugs for low power stuff otherwise use Merit sockets and for fridges and other high load devices use an Anderson, I prefer to charge phones etc with a USB socket.

While I use large cable haven't got a clue what size it is, it doesn't get hot under load so must be okay and the meter reads near the same at both ends..................
 

Dean Anderson

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@Drover Silly question here. If power to the break away and ESC has to be separate to everything else does that mean they need a separate Earth as well as positive? I can use another pin on the 12pin socket for my earth at the car, but will Jayco have a separate earth available?
 
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Drover

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Good point @Dean Anderson , I suppose they are meant to, they are supposed to have power thats independant of the vans battery and a supply thats not shared with anything, I suppose so that if the van battery goes flat they still work . I wonder if they thought about the 12 pin melting down ?

My breakaway power draws from 12v supply to van from tug for charging the battery.

Bit like the breakaway lead, a lot I have seen the tow bar would ploughing the road before it pulls the pin out.