Fridge behaving strange

[WimS]

Hello, I am new here, own an Ocean T6 registered 2020, fabulous car so far, but I experience some strange fridge behaviour:
- It does not work for more than a couple of minutes off grid (so without engine running or connected to external 230V), and only after repeatedly pressing the fridge button
- It works when the engine is running (though I may have to press the fridge button up to 10 times before it works)
- It works when hooked up to external mains power 230V
I just installed 2 new leisure batteries hoping this would solve the issue but it didn't. Voltage on the display is 12.7V, so far away from the low voltage level threshold.

Another strange thing: last weekend we slept in it for the first time, it was connected to the mains. I set the fridge at level 1 but it kept running the whole night and in the morning a water bottle and the strawberries were completely frozen. So looks like something is wrong with the temperature control as well.

Any ideas what I should do? I'm pretty good at DIY, read posts on faulty Danfoss controllers on the T5, is the same controller on the T6? Can it be reached at all?

 

[WelshGas]

Hello, I am new here, own an Ocean T6 registered 2020, fabulous car so far, but I experience some strange fridge behaviour:
- It does not work for more than a couple of minutes off grid (so without engine running or connected to external 230V), and only after repeatedly pressing the fridge button
- It works when the engine is running (though I may have to press the fridge button up to 10 times before it works)
- It works when hooked up to external mains power 230V
I just installed 2 new leisure batteries hoping this would solve the issue but it didn't. Voltage on the display is 12.7V, so far away from the low voltage level threshold.

Another strange thing: last weekend we slept in it for the first time, it was connected to the mains. I set the fridge at level 1 but it kept running the whole night and in the morning a water bottle and the strawberries were completely frozen. So looks like something is wrong with the temperature control as well.

Any ideas what I should do? I'm pretty good at DIY, read posts on faulty Danfoss controllers on the T5, is the same controller on the T6? Can it be reached at all?

The Fridge is exactly the same on the T5 and T6.

Are there any Diagnostic codes on the Control Panel?

For those of you who don't know, if you ever get any problems with roof stuck or any other error say with the heater or fridge, you are able to access the hidden menu in your control panel as used by the VW Engineers.

Access as follows:



1. Hold down the centre of the rotary button together with the menu button (button below with the squares on it)

2. You will get the hidden menu.

3. Rotate the rotary button to get to "VW diagnose" and select this by pressing on the centre of the rotary button.

4. If no errors are present it will display "no errors"

5. If Errors are present then a list of errors will appear

6. Press the centre of the rotary button again to delete all the errors

7. Repeat process above just to check that errors have dissapeared!

8. Re-configure the time and date if neccesary.



Any problems should be resolved assuming these are Electronic and not Mechanical.





Error Codes from Control Panel.





1 = 1 = Pop-up roof

2 = 2 = Plumbing Heating

3 = 3 = Cool box Cooler

4 = 4 = Sewage wastewater

5 = 5 = Fresh water

6 = 6 = Outside temperature

7 = 7 = Battery

Error Code Defect Fault

1010 1010 Short-circuit to (earth) roof

1001 1001 Fuse / short circuit to (plus+) roof

1100 1100 Short-circuit output Roof "on"

1101 1101 Fuse roof "to"

1110 1110 Short-circuit output Roof "to"

1111 1111 Fuse starting Roof "to"

2100 2100 Short-circuit output heating on / off

2101 2101 Fuse output heating on / off

2001 2001 Interrupt input heating 30

3100 3100 Short-circuit output coolbox

3101 3101 Fuse interrupt output coolbox

3001 3001-J698-cooler input error "Active"

3010 3010 Short-circuit input icebox "actual temperature"

3011 3011 Interrupt or fuse input icebox "actual temperature"

4000 4000 Short-circuit to ground water level sensor

4001 4001 Fuse circuit to plus water level sensor failure

5000 5000 Short-circuit to ground water level sensor

5001 5001 Short circuit to plus water level sensor failure

6000 6000 Short-circuit to ground temperature sensor or for outdoor temperature

6001 6001 Fuse / short circuit to plus two temperature sensors for outside temperature

7001 7001 interrupt input interrupt input D +

 

[WimS]

Thanks, it showed ‘No errors’.
(The button below the rotary know has no squares but an arrow back symbool by the way)

I have the feeling that there is a contact somewhere with a high resistance (eg due to corrosion) with causes a voltage drop just about enough to keep the fridge from starting, any idea where to start trouble shooting?

The non-controlled temperature seems to point in the direction of a faulty thermostat , is that integrated in the Danfoss controller?

 

[WimS]

Found the opening in the cupboard next to the fridge and found the Secop 101N0650 controller, will be quite an acrobatic act to get it out it seems

 

[vbk1975]

Thanks, it showed ‘No errors’.
(The button below the rotary know has no squares but an arrow back symbool by the way)

I have the feeling that there is a contact somewhere with a high resistance (eg due to corrosion) with causes a voltage drop just about enough to keep the fridge from starting, any idea where to start trouble shooting?

The non-controlled temperature seems to point in the direction of a faulty thermostat , is that integrated in the Danfoss controller?

Can you take a photo of your "Hardware Menu" screen you get to it the same way as you do the VW Diagnostic one, but scroll up one. Also can you let me vaguely know the temp inside the van. Should look like this, but ignore the numbers in this picture



If there is no fault code my view would be that the Temp sensor has an issue, using this Menu i can try and confirm this.

AN5 is the Fridge Temp Sensor, which is wired directly to control panel, the value is an internal reference, but i have worked out the curve.

As an example AN5=114 is 12.9°C - measured in the fridge.

So if you send me picture or value of AN5 and temperature you think the fridge is, i can check.

 

[WimS]

OK, thanks for your help
Here the Hardware menu, temperature in the fridge is roughly 15-16 degrees Celcius

 

[vbk1975]

OK, thanks for your help
Here the Hardware menu, temperature in the van is roughly 15 degrees Celcius
View attachment 123711

So AN5=107, reflects that the sensor is reporting 6 degrees C.

It doesn't explain all your observations, but this might reflect a defective sensor and this would probably be the first thing i would look at, as it is cheap and can be tested with a new part.

If you are comfortable with doing some basic wiring, I would buy

https://www.amazon.co.uk/gp/product/B01FC4U0JY/?tag=eliteelect-21

and wire it instead of the standard sensor underneath the fridge at the connector, I would just place the Amazon sensor in the fridge next to internal one but in the fridge and see if it fixes it, rather than going to the effort of changing the internal sensor until you have tested this.

A

 

[WimS]

OK, ordered it, should arrive wednesday next week

 

[WimS]

I took a close look at the fridge (no key in, engine off, not connected to the grid, camper control unit on) and was surprised by what I saw:
- even though the fridge was not switched on on the camper control unit, I noticed that it made 3 short start attempts (unsuccesful) every 65 seconds
- I connected a multimeter to the + and - on the secop controller, saw no voltage drop under 12 V during the start attempts
- I hooked up to the grid and the compressor kicked in immediately, even though the fridge was still switched off on the camper control unit
- Only by pressing the I/O button on the camper control unit (so switching it off) I managed to switch the fridge off
- when disconnecting from the grid the fridge keeps running even though it reads ‘switched off’ on the camper control unit


My feeling is: either the secop fridge controller- or the camper control unit is ill, or the connection between the two

NB: voltage drop between leisure batteries and the connection on the secop controller is 0.5V during functioning of the fridge

 

[WimS]

I did some further researching and discovered the the fridge is always switched on if the control display (or camper control unit) is on. If the engine is running or it is connected to the mains it actually cools; if off-grid and engine is off it attempts to start (3 attempts every minute). The only way to stop this is by switching the control display off.
I found exactly this behaviour in the thread 'Fridge permanently switched on', where it was solved by replacing the fridge controller and a relay. This is the same direction that was suggested by our VW Camper Centre in the Netherlands.
As the fridge controller is pretty expensive I first wanted to check whether the relay is faulty. Only thing is: where is it hidden??? I looked in the compressor space but only saw connectors as far as I know.
Does anybody know where this relay is hidden?

 

[vbk1975]

I did some further researching and discovered the the fridge is always switched on if the control display (or camper control unit) is on. If the engine is running or it is connected to the mains it actually cools; if off-grid and engine is off it attempts to start (3 attempts every minute). The only way to stop this is by switching the control display off.
I found exactly this behaviour in the thread 'Fridge permanently switched on', where it was solved by replacing the fridge controller and a relay. This is the same direction that was suggested by our VW Camper Centre in the Netherlands.
As the fridge controller is pretty expensive I first wanted to check whether the relay is faulty. Only thing is: where is it hidden??? I looked in the compressor space but only saw connectors as far as I know.
Does anybody know where this relay is hidden?

so the relay is actually attached to the fridge controller connectors it is an extra black box with a silver label if it is a later van.

 

[WimS]

Could it be this one?

 

[vbk1975]

Could it be this one?View attachment 124101

Yes!!

 

[vbk1975]

Yes!!

So it isn’t actually a relay - it is an electronic switch - @reserves kindly sent me his damaged one to dismantle

 

[WimS]

Interesting! Have you been able to understand it’s function , or to understand what the C,P and T of the controller mean?
I bought this switch yesterday, tried to pull the old one off but it doesn’t move so far.

 

[vbk1975]

Interesting! Have you been able to understand it’s function , or to understand what the C,P and T of the controller mean?
I bought this switch yesterday, tried to pull the old one off but it doesn’t move so far.

@reserves - can you advise how to remove the black fridge relay?

 

[reserves]

@reserves - can you advise how to remove the black fridge relay?

Sorry, just seen this.

Disconnect the wire and it just pulls out directly towards you as you’re looking at it.

 

[WimS]

That’s what I tried, but it doesn’t move the slightest. I managed to get an isolated wire underneath (there is some space there), and pulled as hard as I could, to no avail

 

[reserves]

It will come out. Those 3 connectors are tight.

See if you can get a small screwdriver underneath and pry it out

 

[reserves]

Here's an image of it which might help you figure out how to get it out

 

[reserves]

Those 3 terminals on the back will be tight, but they with a wiggle they will pull out

 

[WimS]

Thanks for your advice, I have not managed yet, the thing is very stubborn
In the mean time I ordered a new fridge controller as well (€80), so in time I will try to replace the whole unit
I was thinking about the functioning of the device, I reckon that that switch is short-circuiting between C and T so the fridge is sort of enabled, and the D/I input determines what temperature should be reached.
On the letters on the controller I suspect D/I stands for digital input, C for common, T for Thermostat, P for protection
What do you think?

 

[WimS]

Following the Penguin diagnosis procedure that I found on this forum I connected the small plus and the D/I to a multimeter and got three beeps indicating Compressor Start Error. As advised I disconnected the power supply for a couple of minutes, then reconnected. No change.

 

[vbk1975]

Thanks for your advice, I have not managed yet, the thing is very stubborn
In the mean time I ordered a new fridge controller as well (€80), so in time I will try to replace the whole unit
I was thinking about the functioning of the device, I reckon that that switch is short-circuiting between C and T so the fridge is sort of enabled, and the D/I input determines what temperature should be reached.
On the letters on the controller I suspect D/I stands for digital input, C for common, T for Thermostat, P for protection
What do you think?

I think D stands for Diagnostic.

You are correct the C and T are connected together but with a resistor in the circuit.

The P is the pin that sets the voltage threshold, again via a specific resistor in the switching black box.