California Ocean T6 Roof Repair

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California Ocean T6 roof repair - Roof will not open/close
TECHNICAL GUIDE

Symptom
When attempting to drive (ignition turned on) or to open the pop-up roof, the central Camping Control Unit (CCU) reports there is a "Roof Fault!", accompanied by audible beeps/pulses. The CCU also won't switch off, alerting that the "Roof is open!" when it isn't.

For the CCU to raise the roof, it needs to be aware of the position of the roof. It does this by using small magnetic sensors called Hall sensors.
There are two hydraulic rams, either side of the roof, that do the lifting and each ram has two of these hall sensors which report to the CCU what position the ram (and therefore roof) is in. The rams are operated by a hydraulic pump hidden behind the CCU, normally heard buzzing away when the roof works normally.

Despite being well covered, after several years the casing of the hall sensors begin to split and normal ambient moist air gets inside them, corroding the magnetic switch, stopping it from working. When this happens, the CCU is no longer aware of where the roof is positioned so, for safety, it blocks the ability to raise or lower the roof.

NOTE: Its good to consider that, even if this hasn't yet happened to your California, this is guaranteed to occur eventually and so it is good to be prepared.

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Troubleshoot
The first thing that can be done is to check if the sensors have perished. To do this in the T6 California, the CCU has a secret menu where the sensor signal can be seen. To access this menu;

• Press SELECT (push down on the control wheel) to bring up the normal menu
• Hold down the BACK (Bottom-right button) and SELECT at the same time, for 3 seconds.
• Choose "Diagnostics"
• Choose "Hardware List"

This then shows a list of all the sensors the CCU listens to;

AN0: Leisure Battery Voltage (Vb Sense) AN1: Battery Current / Shunt (Amps) AN2: External Temperature Sensor AN3: Waste Water Tank Sensor (Grey Water) AN4: Fresh Water Tank Sensor AN5: Fridge Temperature Sensor (NTC Thermistor) AN6: Internal Cabin Temperature Sensor AN7: Unused / Auxiliary AN8: Roof Open Position Sensors <----- AN9: Roof Closed Position Sensors <-----

The two that are of interest are AN8 and AN9. Both of these will show a ZERO, when the ignition is turned OFF. When the ignition is ON, there will be a numerical value shown. In the case of faulty sensors it will show this;




When 255 is displayed, this means a sensor is not detecting the ram position. In normal operation, one of the sensors should be detecting the ram position but in this case, we can see that neither sensors can detect the ram; both "CLOSED" (AN8) and "OPEN" (AN9) showing 255.

Here is what we should usually expect to see as the roof transitions from closed to open, during NORMAL OPERATION.
When the roof is down, the CLOSED (AN9) sensor will show a signal between 106-108 indicating it can sense the ram is close by and the OPEN (AN8) sensor will show 255, meaning it cannot sense the ram near it. When raising the roof, the rams begin to move. Around the half way point (mid-way) both sensors can spot the rams at the same time as they glide through their action, eventually leaving behind the CLOSED (AN9) sensor, making it show 255 and the OPEN (AN8) sensor showing the 106-108 signal that the rams are now next to it.

CLOSED​	MID-WAY​	OPEN​

This behaviour is what we are aiming for, by the end of this project.

Unfortunately, in this tech guide, because both sensors are reporting 255, the CCU cannot tell if the roof is open or closed and will refuse to activate the pump.

This is a problem.

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Repair Options
The goal is to repair the Hall Sensors which, thankfully, is a fairly painless process, but the immediate problem is that the roof is CLOSED. Obviously, if your roof is stuck open, this will be easier for you (if you're not stuck somewhere on holiday), however we shall assume, for the purpose of this guide, the roof is stuck closed and you're in a place where you have some basic tools available and have purchased some Hall Sensors.

NOTE:: The sensors are universal and are used by many car manufacturers to detect the position of convertible roofs on all manner of sports cars etc. The best availability is via the BMW Part Number 54347190735



There are various approaches to getting the roof raised;

• Releasing an emergency hydraulic screw behind the CCU and pushing the roof open by hand, from below
• Manually activating the hidden pump control module by applying a 12v feed to pin 23 on a plug behind the CCU
• Giving a raw 12v feed directly to the pump, bypassing the CCU entirely <---------
• Booking it in with a camper specialist who will raise the roof and change the Hall Sensors (Approx. £600 incl. labour and parts)
• Booking it in with VW who will raise the roof and change the entire wiring loom (Approx. £2200 incl. labour)

Where all of the above are viable options with their own risks/costs, this guide will help you provide a 12v feed directly to the pump so you're able to raise and lower the roof at will, to change the hall sensors.

You will not need to disconnect any batteries from your T6 and you will not need to unplug anything in any particular order. The T6 systems are very resilient and have built in redundancy so feel comfortable and confident to just get on and do it.

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Where is the pump?
Its hidden behind the Camping Control Unit (CCU) and its power plug sits in the headliner (the ceiling padding) to the left of the CCU.
Very understandably, one can immediately think "What? I have to take the ceiling down?" but this is, remarkably, a very simple and easy thing to do.

Headliner
The headliner is kept up there mainly by the sun visors. I personally removed the center console first (see below). The sun visors, when you're ready to, need little covers popped off and unscrewing;

Once a sun visor is released, you will see a cable that operates the vanity mirror light when it is slid open. Gently feel inside the hole and you'll discover a black connector. Unclip this by pulling the little tab outward, not squeezing it inward!

 

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Center Console
The center console needs to be briefly disconnected (watch this video) to allow the headliner to descend with enough space to spot the pump power lead, tucked in to the left.
Once you have the light switches and the CCU out, open the sunglasses holder and undo the screws.

Now, starting from the front, gently tease the entire plastic surround/harness downward and it will begin to POP out of some sprung metal clips that go around the whole edge. It will feel horrible doing it, but its quite safe. The top edge of the surround has two plastic clips that need teasing free.



Disconnect any remaining cables using the very easy clips (or sometimes a little tug) then remove the surround/plastic harness completely.



Once this is all clear, we are looking to the left of the console opening.
Pull down the headliner gently, and peer in from the windscreen side (back of your head against the glass). There you will find a black and purple wiring connector. pull this towards you and, tucked behind that, you will see the pump power connector - very easy to spot because the pumps own cable has a bright white stripe on it!

Gently tease this forwards and unclip it. The connector side we want is the one with the white stripe. Its cable might be tucked behind the screw that holds in the long black module you can see, which actually does all of the controlling of the pump systems. Just hook it out - everything is super durable in here so don't feel you have to be too gentle. feed it over to the big hole where the console usually is.

Now, apply your 12v feed to these two connectors. It doesn't matter which way around as the pump will simply operate either way. One of them will be opening, one closing.
Personally I used a 30amp fused 10AWG lead connected to the leisure battery under the passenger seat and i crimped two crocodile clips to them, of different colour so I could switch them around.



When the pump whirrs into action, let it run for 3 seconds to check which direction its pumping (opening or closing the roof). This will not damage the pump or the hydraulic pipes as the CCU does this anyway, when opening or closing the roof itself - it runs it an extra few seconds at the end to ensure its locked in place etc.

 

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Hall Sensors
These are very quick to locate and to repair. Many fabulous people have posted photos of how this is done, on this forum, but I will also add my own, to complete this particular guide.

Now you have the roof open, it will stay open as the hydraulics are in place and the roof is firmly and fully open. If you havent operated the roof for some time, perhaps check all is well by allowing the roof to stand open for 20 minutes and check its not slowly closing. Its highly unlikely it will, but worth being careful.

Hop up on some step ladders and have a look at the rails that the lifting arms sit on. Along it you will see black plastic covers. There will be a slightly proud cover with a single Torx T20 screw.

Lift the cover upward from where the screw hole is, then slide it backwards (to the left, in these photos) as the other end has a small cup shape at its base, which tucks under the ram cylinder. Then you can lift it away.

The Hall Sensors are small black cubes with little plastic arms that secure them.. They are found sitting underneath each of the hydraulic connectors. Here, you can see my warped and cracked front hall sensor (nearest the drivers seat).



The sensors are not screwed in and can be lifted out easily but, as you can see, the hydraulic connector is preventing the hall sensor from being removed. Its necessary to loosen up the hydraulic line so we can rotate it out of the way. Snip the tie-wraps holding the hydraulic lines, unhook the rear by firmly tugging upwards, then rotate the hydraulic connector out of the way.

Now lift out the dead sensor, prising the little black arms. It pops out very easily.

The crack in the sensor was easy to split open. Within you can see it is rusted beyond functional use.

 

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Replacement Hall Sensors
Hopefully you have 4 little bags of Hall Sensors

Firstly, lets cut off the old one. I cut close to the sensor so there would be plenty of the T6 wire available. Remove some of the insulating tape then use a 0.8mm wire stripper (or your teeth!) to provide a clean end. As others have mentioned, there aren't many strands inside these thin wires but they are high quality. Try not to cut any of them (hence the use of wire strippers!)

Grab yourself a new sensor and press it into the hole where the old one was removed. Choose what wire length you'd prefer (I didn't shorten mine at all and it very happily sits curled inside the casing when all finished), strip the ends, again, using the wire strippers at 0.8mm (20AWG) then twist the wires together, sealing them with tape. I've chosen green because I love colour!

 

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Testing the new sensors
At this stage you likely want to see if its possible to check if you have found the culprit sensor and are keen to test the roof. You may be looking at the headliner thinking it would take an age to reassemble everything so a test can be made. Thankfully, we don't have to do that!

Find your unplugged CCU and immediately plug in the black and purple connector, paying attention to the purple lever and ensuring it sits up vertically as you go to plug it in, so it can do the clamping action properly. It will want to flip over and secure itself, as you press down on the black plug.



Press the SELECT (push down on the wheel) several times to skip setting the time and date. Go back into the Diagnostics menu (Press SELECT and BACK for 3 seconds).

• Choose "Diagnostics"
• Choose "Hardware List"

Turn on the Ignition so there is power to the sensors. With any luck, the OPEN (AN8) sensor will be showing the 106-108 value suggesting it detects the ram nearby because the roof is open.



This will be enough to detect the roof is open and the controller will allow the roof to close, using the normal CCU menu options, once the pump power connector is back in its normal place. However, do check the state of the remaining sensors. Any cracks in their casing is a sign they should be replaced.

The front sensors share a negative (ground) so if one is shorted (rusted and cracked), it will stop the rear sensors from working normally. Because you still have the direct 12v connection to the pump, lower the roof and watch the values in the diagnostics menu and check they match NORMAL OPERATION as shown near the beginning of this guide. You should see AN8 and AN9 transition normally as the roof lowers, with the CLOSED (AN9) sensor showing a steady 106-108 and the OPEN (AN8) showing 255.

If this is not the case, keep replacing the hall sensors until these values do behave normally. At no time should you reassemble your van until the values behave normally. Keep the faith - they will eventually!

NOTE:: The rear sensors are a little tricky because the hydraulic connector has less slack in it to rotate it out of the way. Its definitely possible to change them and others have reassured the connector is very firmly installed so tug a tiny bit further than you would normally. Others have just removed the black plastic legs and slid the sensor in that way. See how you get on!

Once all sensors are checked and the AN8 and AN9 values are showing normal operational behaviour, you can now reassemble your T6! Do everything above, but in reverse.

I took 4 hours to do the whole thing, including changing two sensors. My two front sensors were both cracked. The rear sensors appeared to be good/undamaged. I hadn't operated my roof for 2 years and all hydraulics worked perfectly fine.

Take your time! Enjoy the small project. Its fun to see how simple it turns out to be (and a healthy challenge).

 

[Chriskend]

Absolute cracking job