Starcraft Jayco Outback Starcraft Solar

Drover

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@Drover, there is no way a single 160w solar panel can meet the constant demands of a 3 way fridge requiring more than 14 amps at 12 plus volts constantly. Okay to try to keep storage battery topped up when fully operating, but at 5 amps and varying all the time on the road - shadows and non optimal direction - no way. Even with 15 amps solar capacity, this input is not constant and always needs the back up of some sort of storage system eg battery voltage and current.
NO,No,NO I mean 12v from tug for charging batteries not for running the fridge, goodness me did you think I fell off the branch ??.......:crazy:

We all know a 3 way fridge cannot run off the van batteries well not for long and a 160w panel isn't going to keep up with drain anyway ......... though if your only driving for 4 hours or so at a time hardly any need to run the fridge on 12v from tug anyway, have done it many a time in various temps and not a big drop at all so long as the door stays closed............... So @Hitting the road just meaning no need for battery charging, in these modern vehicles with electric everything cutting back loads is important for alternator and start battery life, auto lights, wipers, heated seats and all the other things especially electric steering means the vehicles power grid gets a flogging, electric steering can demand up to 80amps at times so making sure items not in use are turned off is a help... auto headlights that come on each time you start up in a garage place a huge demand on things in the beginning along with AC and other auto bits so while running the fridge is a big demand adding battery charging is just an uneccessary load if you have solar ...

The other point I was going to make is if your going to be mainly off grid, I would be adding another panel to the roof or a portable, or have we mentioned that already...???
 
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Hitting the road

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I am a bit gobsmacked finding the demand is so high for power at 12v for the 3 way fridge...but I guess due to the way an absorption fridge operates it makes sense.. Little wonder the wiring is set up the way it is to drag the power from the tug's alternator. Worth knowing though to keep in mind...
 

Drover

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I am a bit gobsmacked finding the demand is so high for power at 12v for the 3 way fridge...but I guess due to the way an absorption fridge operates it makes sense.. Little wonder the wiring is set up the way it is to drag the power from the tug's alternator. Worth knowing though to keep in mind...

My Dometic RM4605 likes to chomp on 275w/23amps so would make short work of any battery without an alternator hanging off it, the smaller fridges seem to be around the 175w/14amp draw, it has 6 B&S cable huge stuff, so when towing I don't run anything thats not really needed, its basically a kettle element without the water, it also chews a bit more Gas than the smaller units so I work on 7 days for a 8.5 bottle to be safe, the math says 10 days but with cooking you never know so 7 is a good time line, the fridge draws the same amount all day every day its a constant. If you use swap bottles you know you have 8.5 but a refill rarely is done by weight so you never know if they have shut off early so I always have the bottle full again in a couple of days, I have even carried an empty with me for extended stays swapping it at a nice price in a major town before venturing out where it would be $40 or more, so 3 bottles gives me 3 weeks ...... while I like to support the outflung towns $50 for a bottle of gas stretches my budget a bit too much. Thargomindah is good at least they weigh your bottle and only charge for the gas which is great when you just want to top up when no gas further on.

Wiring up the vehicle now does require an understanding of the BMS system that applies to that vehicle, some need the Neg to be ground on the chassis eng/battery ground as connecting to battery Neg terminal plays merry hell with things and kills the battery while others are quite happy, others will work well if Pos to main battery Pos terminal but again will cause drama if connected elsewhere...... Not just hook ups for vans/campers even doing spotties can cause things to throw a hissy, I try to stay away from doing them for friends/family now, gets so complicated nowadays, working on the young blokes EH was a dream no BS wiring....


PS: just looked at the specs for your Thetford its very economical on gas and 12v compared to my Dometic by miles, really bluddy good.
 
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Hitting the road

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PS: just looked at the specs for your Thetford its very economical on gas and 12v compared to my Dometic by miles, really bluddy good.

Nice to have a win somewhere for a change...

I'll have to check which pin in the Anderson plug runs the fridge and check where it is connected via the Anderson plug on the tug. The whole thing was wired up when i bought it and when plugging the van in everything worked fine. Has been no indication of any dramas supplying that power, but just to be sure all is well I'd like that particular connection to be fused. Will be a job for my favorite Auto Leccy me thinks...

I have no idea how much off grid time I'll get using gas for the fridge, water heater and cooking together. That will be a suck it and see, just making sure when planning the next off grid excursion I start with two full gas bottles...
 

Drover

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I have no idea how much off grid time I'll get using gas for the fridge, water heater and cooking together. That will be a suck it and see, just making sure when planning the next off grid excursion I start with two full gas bottles...
A quick roughy of how long for fridge out of a 8.5 bottle, thats hoping the specs are correct is about 20 days, twice mine so with cooking, HWS I owuld hazard 14 days, secret is you only turn the HWS on when you want it, never leave it on all the time as it will fire up every so often, not actually sure how much you would use if left on but its a pain in the bum roaring away during the night.. (thats a surburban unit ) I did the maths and then on a long camp by a river 8 days it took to empty and sort of around that ever since, probably get a extra day if didn't use the HWS, yours would certainly get a few more days..... The Thetford is in grams per hour so my maths could be wonky as well...my Dometic is in Mj/hr so I cheat and use a online abacus.... Check on the fridge tag for use and if you want to roll your eyes, then here; https://www.elgas.com.au/blog/389-lpg-conversions-kg-litres-mj-kwh-and-m3/


Actually when you had it plugged in and you checked if the van was getting a charge did you have the engine running ??? Supply could be shut off or the pins are different, always a good idea to have someone turning the knobs in tug while you probe the plug with multi meter checking the tug 7/12 pin then you remove the cover off the van plug and plug it in and cross check the connections on it ..... sometimes a different pin may be used or not even connected..... it pays to check it all even if no problem, at home for checking and looking in comfort, so on road you know where to go and don't have to waste time trying to figure things out.............. and my catch cry "Always check the wheel nuts before you head away and always after someone has worked on it whether the wheels were touched or not", many have come croppers because they assumed the service bloke did it...

So thats it from me, read the manual and poke and prod everything, knowledge is always handy................................... Search about HWS checks next....:becky:
 
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Hitting the road

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Thanks heaps Drover...as you observed, the fridge specs do give the gas usage as 420g per 24 hours, so if I have 8500 grams in a cylinder you are right it equates to about 20 days use. But real life is always different from theory hey, so I'd be agreeing with you at counting on maybe 14 days when using all gas appliances. Extra days would be a bonus...I didn't ask the bloke I bought it from of his experience...should have done as they did the big lap in it, but I think they also stayed mainly in van parks.

I am looking forward to getting away from my office to actually get to test all this stuff. The next excursion we have planned in a few weeks involves staying at van parks with friends so will be using the Park's power...

With regard to the electrical connections, I can't recall whether I had the engine running or not when the fridge came to life on 12v...it was plugged in though. That is another thing i will investigate. But I do recall that when i have pulled up and turned the engine off the fridge was still showing as running on 12v in the van. (green light glowing)
Be definitely worth keeping that in mind too, if i decided to stay put for a few hours and left it running on 12v, it could be embarrassing when eventually hitting the go button and getting no response...

The mate where I keep the van is a van owner and a bit of a whiz kid to boot, old school like the rest of us, so between the two of us we'll get it figured out...
 
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Boots in Action

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Thanks heaps Drover...as you observed, the fridge specs do give the gas usage as 420g per 24 hours, so if I have 8500 grams in a cylinder you are right it equates to about 20 days use. But real life is always different from theory hey, so I'd be agreeing with you at counting on maybe 14 days when using all gas appliances. Extra days would be a bonus...I didn't ask the bloke I bought it from of his experience...should have done as they did the big lap in it, but I think they also stayed mainly in van parks.

I am looking forward to getting away from my office to actually get to test all this stuff. The next excursion we have planned in a few weeks involves staying at van parks with friends so will be using the Park's power...

With regard to the electrical connections, I can't recall whether I had the engine running or not when the fridge came to life on 12v...it was plugged in though. That is another thing i will investigate. But I do recall that when i have pulled up and turned the engine off the fridge was still showing as running on 12v in the van. (green light glowing)
Be definitely worth keeping that in mind too, if i decided to stay put for a few hours and left it running on 12v, it could be embarrassing when eventually hitting the go button and getting no response...

The mate where I keep the van is a van owner and a bit of a whiz kid to boot, old school like the rest of us, so between the two of us we'll get it figured out...
I have a VSR in line between the tug battery and the van fridge circuit which is independently connected by heavy cabling and Anderson plugs. Was simple and easy to fit and now do not have to think about current draw to fridge (about 15 amps) when I turn off engine. Beats my memory every time!!
 

Drover

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A fridge switch is a must for sure, I will eventually fit one one day, I just unplug never forget as I always do a walk around when i pull up remonder to plug in again is a blank rear cam screen.

Park is the time to play with everything that opens, closes or goes zap, check drain operation, a well set up sink drain will suck a chux down the hole in a second or 2, if not add reroute and clean drain hoses to the mod list....................... dont forget the wheel nuts either, make sure you actually have a jack and most importantly that it will lift a wheel when you are loaded, that can be a surprise to find ...
 
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Hitting the road

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A fridge switch is a must for sure, I will eventually fit one one day, I just unplug never forget as I always do a walk around when i pull up remonder to plug in again is a blank rear cam screen.

Park is the time to play with everything that opens, closes or goes zap, check drain operation, a well set up sink drain will suck a chux down the hole in a second or 2, if not add reroute and clean drain hoses to the mod list....................... dont forget the wheel nuts either, make sure you actually have a jack and most importantly that it will lift a wheel when you are loaded, that can be a surprise to find ...
Agree...the sink drains are on my hit list as they both take time to drain, likely due to the silly convoluted 1" hoses they use! I'll never understand why they have to use those dinky little drain outlets either with a plug the size of a 20c piece. No doubt the sinks and plumbing are super light yes, but how practical.

Wheel nuts...very important eh...I have had all the wheels off already checking wheel bearings and play so are all good...had to nip a couple of bearings up. I carry a hydraulic bottle jack for ease of use and versatility. In fact wouldn't even know what the standard Jayco jack looks like...if there is one.

I'll seriously consider too a fridge switch, fitting a VSR is a great idea, especially if that 10 minute road side stop turns in to a 3 hour stop...oops. Just have to find where that the live 12v feed is as it snakes it's way toward the fridge from the Anderson plug so as to break in to it somewhere.
 

Drover

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Agree...the sink drains are on my hit list as they both take time to drain, likely due to the silly convoluted 1" hoses they use! I'll never understand why they have to use those dinky little drain outlets either with a plug the size of a 20c piece. No doubt the sinks and plumbing are super light yes, but how practical.

Wheel nuts...very important eh...I have had all the wheels off already checking wheel bearings and play so are all good...had to nip a couple of bearings up. I carry a hydraulic bottle jack for ease of use and versatility. In fact wouldn't even know what the standard Jayco jack looks like...if there is one.

I'll seriously consider too a fridge switch, fitting a VSR is a great idea, especially if that 10 minute road side stop turns in to a 3 hour stop...oops. Just have to find where that the live 12v feed is as it snakes it's way toward the fridge from the Anderson plug so as to break in to it somewhere.

The drain hose size is actually quite good its the way they run it is the biggest problem, on my 14.44 the sink drain plug was a 90deg job, once that was changed to a straight drop and the hose all relaid to miss a drawer and no low spots it would pass the chux test, even with gurgle, so its not the hose.... My 14.44 thread as well as Big Mal thread shows the grey water tanks I made so everything runs into them and it then runs out via a 25mm gate valve or can be closed..............................

I prefer a Fridgeswitch than a VSR mainly because it works on motion, is simple to fit and doesn't have drama with some vehicle wiring set ups like a VSR can especially in these modern vehicle systems where everything is electrical.... I much prefer the load to be shut in a few minutes than when the battery has dropped to a certain level.... manual stick not a biggy but an auto........aarrgghh... hence why I carry a jump starter.

 
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Hitting the road

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The drain hose size is actually quite good its the way they run it is the biggest problem, on my 14.44 the sink drain plug was a 90deg job, once that was changed to a straight drop and the hose all relaid to miss a drawer and no low spots it would pass the chux test, even with gurgle, so its not the hose.... My 14.44 thread as well as Big Mal thread shows the grey water tanks I made so everything runs into them and it then runs out via a 25mm gate valve or can be closed..............................

I prefer a Fridgeswitch than a VSR mainly because it works on motion, is simple to fit and doesn't have drama with some vehicle wiring set ups like a VSR can especially in these modern vehicle systems where everything is electrical.... I much prefer the load to be shut in a few minutes than when the battery has dropped to a certain level.... manual stick not a biggy but an auto........aarrgghh... hence why I carry a jump starter.


I'll have to stick my head under the sinks and have a look, the drain pipes probably do a couple of 360's before going in to the grey water tank. I initially thought it might have been an air lock when draining in to the grey water tank with the valve closed, but it still does it when the grey water tank valve is open. Just another one of the numerous jobs that I have to get on to...

Interesting, fridgeswitch, i didn't even know such a thing existed until I googled it just then.
 
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Drover

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In my 14.44 I redid my water lines and drains, pressure was rubbish and they drained slow, everything ended up shorter, less bends and ran faster....................

In my 14 wired a normal old relay to the fridge 12v supply, the relay was activated by the parkers, I always drove with them on and when I got out of the car the chimes went off , so I turned lights off, the fridge went off as well.... that was temporary till I got a fridge switch, still haven't ... You can also piggy back a relay to the DRL's unless the BCM/ECU has a hissy about power use.... any ignition on source really...
 
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Hitting the road

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Good thinking...The thing I have to determine is which terminal in the Anderson plug is the live one for the fridge. Once I do that i can look at fusing the supply side. I do like the simplicity of adding in a VSR before the fridge in the van, even though as you point out it will supply until voltage falls.

Though thinking sideways, would a VSR be fooled due the "smart" alternator voltage dropping as the ECU instructs it once the start battery is recharged after start up, and opening the circuit thus isolating the fridge. I guess I wouldn't really know until fitting one up and carrying out voltage readings.
What do you reckon?

Would the fridgeswitch being sensitive to movement keep switching power on due to the van rocking while stepping in and out?
 
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Hitting the road

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I really need to find for sure whether the fridge still operates on 12v when the engine isn't running. Maybe the feed from the Anderson plug stops when the key is off? Anyway, from that info it will determine what i might need to do...
 

Drover

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I have to determine is which terminal in the Anderson plug is the live one for the fridge.

Though thinking sideways, would a VSR be fooled due the "smart" alternator voltage dropping as the ECU instructs it once the start battery is recharged after start up, and opening the circuit thus isolating the fridge. I guess I wouldn't really know until fitting one up and carrying out voltage readings.
What do you reckon?

Would the fridgeswitch being sensitive to movement keep switching power on due to the van rocking while stepping in and out?
The anderson plug has a "+" and a "-" symbol stamped on them .................................... it really depends on the vehicle system, some it doesn't matter one bit but a VSR fitted somewhere in the line is a join, far better at the fridge terminal really, less joins/connections less resistence and voltage loss........... The Fridgeswitch with movement in van at lunch stop has been on my mind but to date have heard nothing and so I would doubt it is an issue...
I really need to find for sure whether the fridge still operates on 12v when the engine isn't running. Maybe the feed from the Anderson plug stops when the key is off? Anyway, from that info it will determine what i might need to do...

Well it depends on where a switch was fitted, van or tug, van is usually at back of fridge, tug is anyones guess, I suppose hook up run on 12v then shut off engine and see what happens, fridge may eventually go to fault or keep running and that will be your answer, Fridge switch type unit it will shut off in 3 mins, a VCR you could be waiting for ages, using a multi meter won't help as the fridge dash lights will tell you..... if you know your tug so if nothing at back of fridge I would say you don't have anything.... not something to really panic about anyway if Im stopped somewhere for a few hours I pull all the plugs anyway and turn the gas on so the fridge will run ......... and as a safety measure I always check the whole rig, plugs, gas off, coupling connected before moving off, some people think its a joke to pull a pin, brick a wheel or something, had it happen in trucks so always check things if I have been away from it, no matter how long.. always do a walk round tyre kick when you stop and before you get going again no matter how long....... tyre can deflate while your watering the plants.
 
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Boots in Action

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The drain hose size is actually quite good its the way they run it is the biggest problem, on my 14.44 the sink drain plug was a 90deg job, once that was changed to a straight drop and the hose all relaid to miss a drawer and no low spots it would pass the chux test, even with gurgle, so its not the hose.... My 14.44 thread as well as Big Mal thread shows the grey water tanks I made so everything runs into them and it then runs out via a 25mm gate valve or can be closed..............................

I prefer a Fridgeswitch than a VSR mainly because it works on motion, is simple to fit and doesn't have drama with some vehicle wiring set ups like a VSR can especially in these modern vehicle systems where everything is electrical.... I much prefer the load to be shut in a few minutes than when the battery has dropped to a certain level.... manual stick not a biggy but an auto........aarrgghh... hence why I carry a jump starter.

@Drover, I agree with some of the things you say about Fridge switches working on motion. However, IMHO there is a problem when the vehicle is not in motion, (notwithstanding the short delay before it shuts off power) in say at long traffic lights, waiting at a crossroad, or at road construction points- sometimes for several minutes - or stopped in traffic jams for lengthy periods, points brought up by another member on this forum. During these times, there is no power to fridge at all. At least with a VSR, the fridge is always receiving power (unless battery voltage drops below 12.6 volts - most unlikely while engine is on!). There is also the advantage that fridge load is not in circuit during engine cranking and only connects the fridge load when battery/line voltage exceeds 13.4 volts. A 15 to 20 amp load on top of everything else during starting would certainly test a weakened battery, especially as you say "on modern vehicles when every thing is electrical". And there is no difficulty in fitting a VSR on the fridge line even on modern cars - just a fused active line in from battery, through a voltage sensitive relay and an output line to fridge, and can be fitted in any position, and other circuits can also be through the relay if necessary. Of course a good earth is necessary to ground the relay. No more difficult than fitting a Fridge Switch in van, only 3 connections and large bolt on connections for heavy cabling IN and OUT. A VSR is really just one step above a manual ignition switch with the advantage that you do not have to remember to turn switch ON and OFF, and high current is not going through the ignition switching system/relay.
I, at least have that VSR fitted to my tug for my dedicated fridge line and can vouch for their operation. I understand that you have neither a Fridge Switch nor VSR for your fridge, and rely on fridge insulation to maintain cold and a rear camera connected to the fridge line to tell you your fridge is receiving power. That means that you do not have to rely on memory like people like me who have to depend on simple technology to keep fridge going all the times when on the road, whether moving or stationary.
 
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Drover

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@Drover, I agree with some of the things you say about Fridge switches working on motion. However, IMHO there is a problem when the vehicle is not in motion, (notwithstanding the short delay before it shuts off power) in say at long traffic lights, waiting at a crossroad, or at road construction points- sometimes for several minutes - or stopped in traffic jams for lengthy periods, points brought up by another member on this forum. During these times, there is no power to fridge at all. At least with a VSR, the fridge is always receiving power (unless battery voltage drops below 12.6 volts - most unlikely while engine is on!). There is also the advantage that fridge load is not in circuit during engine cranking and only connects the fridge load when battery/line voltage exceeds 13.4 volts. A 15 to 20 amp load on top of everything else during starting would certainly test a weakened battery, especially as you say "on modern vehicles when every thing is electrical". And there is no difficulty in fitting a VSR on the fridge line even on modern cars - just a fused active line in from battery, through a voltage sensitive relay and an output line to fridge, and can be fitted in any position, and other circuits can also be through the relay if necessary. Of course a good earth is necessary to ground the relay. No more difficult than fitting a Fridge Switch in van, only 3 connections and large bolt on connections for heavy cabling IN and OUT. A VSR is really just one step above a manual ignition switch with the advantage that you do not have to remember to turn switch ON and OFF, and high current is not going through the ignition switching system/relay.
I, at least have that VSR fitted to my tug for my dedicated fridge line and can vouch for their operation. I understand that you have neither a Fridge Switch nor VSR for your fridge, and rely on fridge insulation to maintain cold and a rear camera connected to the fridge line to tell you your fridge is receiving power. That means that you do not have to rely on memory like people like me who have to depend on simple technology to keep fridge going all the times when on the road, whether moving or stationary.


Quite valid points but the Fridgeswitch is off while your hooking up and won't be activated until the vehicle is moving so no load on cranking battery at all and shutting down in long roadworks or traffic isn't any sort of drama as fridge isn't going to get warm, forgot to turn mine to auto/12v a few times and hours later its 1deg higher........................ Cam only shows power, not if some idiot pushed the correct buttons.:confused: I still have to look at panel to check if its actually working on 12v.

A Fridgeswitch would have to be fitted at back of fridge but a VSR fitted to jeep wouldn't be a bad idea in some ways for me, as the Anderson on the tug is used for other stuff as well, not always with engine running so could save a memory lapse ...........
I do wonder how things go with these stop start vehicle, now they would be a pain towing...................... A good reason for a compressor fridge, another reason to do away with the vehicle hook up..... if the van can't run the fridge as it goes down the road then fat chance in camp.
 
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Hitting the road

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Hmmm, I was wondering whether a "smart" alternator could fool a VSR...evidently so;


When all else fails, read the user manual... In the user manual for the Thetford fridge type in the van and I came across these:

"Operating on 12v is only effective while the engine of the vehicle is running" (That may mean amperage could be insufficient otherwise?)

"In case the refrigerator is installed in a caravan, the refrigerator needs a D+ signal (engine running) from the towing vehicle to operate in DC mode while traveling"

So maybe the fridge is smart enough to turn off when the engine turns off? As you wrote Drover, if parking for an extended period you'd switch to gas anyway...

I will have to be a little more observant next time out...
 

Drover

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The D+ is on all auto fridges, it is just a low power circuit which signals to the fridge brain that 12v from tug is available so when it does a search of available sources it will go to 12v if the other 2 aren't available, sometimes if the fridge wiring is run direct from tug by passing the 7/12 pin as that connection is removed from fridge the D+ is forgotten so fridge won't work off tug until its connected up again....................... and Yes in some vehicle set ups and depending how you connect the VSR it may have some dramas but thats vehicle specific and there are work arounds so I believe.

Youv'e given me the idea that it would be a good spot for the Fridgeswitch to hook into , something to think about...
 
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