Quote: wooliew wrote in post #26

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Skoda just don’t have the wiring loom to provide a supply to the fridge contacts in the socket.

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Our 2017 Skoda Kodiaq has all 13 functioning, when I asked Skoda if all were working they replied no the fridge wouldn't be wired, so I took it to a local fitter who said he would work out how get the wires through, I had only left him for 5 mins when he rang to say they don't know what they are talking about, it's all wired up correctly.
Dave

The upgraded fans were a Skoda recommendation, it was my choice whether or not to have them fitted.

Yes, pins 10 and 11 have no conductors and are not connected. The dealer has also confirmed not connected as it is Skoda policy not to do so.

As some Soda Yeti models have a 12V socket in the boot may the wiring is already be there to be used for the fridge ?

The 12V socket is/was a standard item on certain spec. Yeti's, the towing preparation kit was always a cost option, so it depends whether the initial buyer or dealership specified it. All Yeti's had GTW on their VIN plate whether they had towing prep. or not. The towing prep. loom ends up with two different connectors tucked away behind trim in the boot but I've no information about what those different connectors actually power. As said, a call to P F Jones may clarify as they'll be dealing with these cars on a daily basis.

I have had three Skodas, each had 12v socket in the boot, very useful too, particularly for running a cool box because the fridge in the caravan doesn’t operate in transit.

I don't know if this will help??? I have a 1994 Eriba Familia.
When connected to my Landrover the hitch tilts the fridge over 3 degrees, which is the maximum for the fridge to work, over around 3 degrees and the fridge will not work on any input.
Also there is often a relay in the towing vehicle which only sends 12 volts to the fridge when the voltage is above around 13v, often only achieved when the engine has been running sometime.So far I have not discovered how to observe this while driving. I am wondering wehether to bypass the relay with a switch, has anyone done this?

Don't like the idea of bypass switches at all. Flat batteries come to mind. The concept of only supply power to the fridge when the tow car is up and running and able to provide that extra power is sound and should not be by-passed.......in my view.
The fact that your towing height is less than perfect will have absolutely no bearing on a by pass switch. If the fridge aint level it aint going to work properly no matter how you power it.

As for observing the power supply voltage, I dis this on my Seat Ateca by inserting a 12Vdc meter in the "cigar lighter" whilst driving around. With no caravan the voltage varied from 11.5V to 17.5V thanks to the modern smart alternator. When the caravan is connected, thanks to the properly installed electronics and programming, the voltage was a steady 14V which the fridge and battery could cope with.

Hi. Does anyone have experience of using a continuous 12V supply across pins 9 & 13 to power van electrics please? I am trying to find out if it should work or whether I have a problem with my van's electrics.

Van - 540 Troll 2019
Car 1 - BMW (2016) with factory fitted-tow ball and 13 pin electrics
Car 2 - Volvo (2020) with factory fitted-tow ball and 13 pin electrics

The BMW has continuous 12V supply across pins 9 & 13 (measured with multi-meter) but, when connected to the van (engine off and on) and with the leisure battery disconnected, I see no evidence of the 12V being used by the van. I have not detected 12V from the switched supply across pins 10 & 11.

The Volvo seems to deliver a switched 12V supply (presumably across pins 10 & 11) as it runs the fridge when the engine is on and with the leisure battery disconnected. I checked it was cooling with a thermometer.

So I know the fridge will cool when there is a switched 12 V supply (presumably across pins 10 & 11) but want to get answers to these questions:
1) Should my van be wired to use a continuous 12V supply (across pins 9 & 13) and
2) if yes, which circuits will be supplied?

Quote: Bob wrote in post #41

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Hi. Does anyone have experience of using a continuous 12V supply across pins 9 & 13 to power van electrics please? I am trying to find out if it should work or whether I have a problem with my van's electrics.

Van - 540 Troll 2019
Car 1 - BMW (2016) with factory fitted-tow ball and 13 pin electrics
Car 2 - Volvo (2020) with factory fitted-tow ball and 13 pin electrics

The BMW has continuous 12V supply across pins 9 & 13 (measured with multi-meter) but, when connected to the van (engine off and on) and with the leisure battery disconnected, I see no evidence of the 12V being used by the van. I have not detected 12V from the switched supply across pins 10 & 11.

The Volvo seems to deliver a switched 12V supply (presumably across pins 10 & 11) as it runs the fridge when the engine is on and with the leisure battery disconnected. I checked it was cooling with a thermometer.

So I know the fridge will cool when there is a switched 12 V supply (presumably across pins 10 & 11) but want to get answers to these questions:
1) Should my van be wired to use a continuous 12V supply (across pins 9 & 13) and
2) if yes, which circuits will be supplied?

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Thanks for the input and I apologise if my intentions were not immediately clear.

I am planning a long European tour later in the year with my BMW towing. I want to find a way to keep the fridge chilling whilst I am towing.

I totally understand that I will not be able use the car to power the van fridge when pitched. What I am trying to find out is whether my van can make use of the 12V continuous supply from the car (across pins 9 & 13) when I am towing.

Hi Bob

For reference, the manual for the Schaudt CSV409 12V distribution unit is saved in the forum's technical help section, here.

The schematic (page 14) shows the 2 inputs from the towcar: permanent 12V (usually referred to as B+), and switched 12V (usually referred to as D+).

The schematic shows input B+ is gated into the CSV's booster circuit by D+ via a relay.
(The booster increases the car's 12V to a steady 14.25V to charge the leisure battery).

So B+ requires the engine running to charge the leisure battery via the booster.

Note that switched 12V D+, de-energises the habitation latching relay to switch off the caravan's 12V habitation consumers (lights etc, but not including the low current supply to keep the fridge running).

So when the engine's running, permanent 12V charges the leisure battery and keeps the fridge 'alive', and switched 12V is supplied to the fridge 12V element to allow cooling.

(The latching relay is also energised/de-energised by operating the caravan's 12V on/off switch).

I've never tried switching on the caravan's 12V when the car is connected and running (why would I?) so I don't know if doing this will switch the habitation consumers back on.

I hope this helps to answer your questions, Bob.

John
Most helpful... thank you.

I freely admit that I am on the limit of my understanding but from your answer, and a look at the block diagram, it seems to me that the towing vehicle will only ever charge the leisure battery and energise the fridge controller (cooling) when BOTH the permanent live (9 & 13) and the switched live (10 & 11) are present (in the tow bar electrics) and energised by the towing vehicle (with ignition/engine on and with the alternator allowing current to flow to the van, i.e. not prevented by some "smart" function that prioritises the towing vehicle battery).

So it also seems that my vehicle will not even charge the leisure battery whilst towing (never mind chill the fridge) unless all of the above conditions are met.

Do you concur?

Thinking about the behaviours seen with my Volvo (see earlier post - fridge definitely chilling when connected with engine running) then it seems that my Volvo tow ball has been fitted with the full 13 pin wiring harness. Great...that's 1 of 2 sorted! What's more, the fact that I wasn't able to detect the continuous 12V supply on the Volvo socket is probably due to the car being relatively new, being equipped with a "smart" alternator and me conducting my testing shortly after starting the engine.

Do you concur?

As for my BMW, I think I'll need to get the tow-ball socket opened to see what's inside and go from there.