Sagging Roof bellows in hot weather - experiences

[vbk1975]

I would never presume that to work. If I was programming the system, it would be like:

1. Car is turned off
2. Is roof up? Yes - start timer. No, do nothing.

To extend this slightly, i think this is the likely sequence

Autocorrect

1.Use Button to open roof, Roof Opens, Both Open Sensors Detected, Release Button (Or Hold) and Pump keeps going until roof pressurised. (Electrical Current exceeds the number of Amps that is required to drive against the check valves)

2. Ign Off (Timer starts)

3. After X mins roof is checked.

- If Roof Sensors are showing fully open - do nothing

- If Roof Sensors are not recording fully open - drive pump until sensors recorded and roof pressurised.

Keep repeating 3. every X mins (First check and subsequent check times could be different)

If Ign is switched on, then cycle starts again at 2(ie timer reset) when Ign is switch off.

if Roof Lowered by User (Button) then No Auto Correct

 

[DianeM]

Lights out, they went out as we went to bed and the autocorrect kicked in during the night.

Our roof has dropped about 3cm a day measuring at the stiffened part just at the end of the mattress, on the passenger side, 1cm on the drivers, it has never auto corrected we haven’t left it any more than that as it would make lifting the roof bed awkward, we have lowered and reset ourselves as we are not willing to leave it any longer, we have had no issues with lighting.

View attachment IMG_0008.jpeg

 

[DianeM]

The auto correct works seemlessly when you leave the vehicle alone. Put the roof up, take the keys out and at 10 hours it will re-inflate if necessary. And then at every 5 hours. Once it doesn't need to correct it never checks again.

Whilst not documented, the timer appears to be disabled by turning the ignition on. I think there are other functions that also cause this reset.

I think the TPI is documented in this thread in that the roof has to fall 20cms in 72 hours. Of course leave the vehicle alone and it auto corrects so you never meet the VW criteria. Unless it's massively broken.

Also I think autocorrect only kicks in at the point the lights switch off. So if they switch off at 10 hours and 1 minute, no re- inflation.

There are a lot of I thinks there, if I was sleeping under a roof that had dropped 20cm I’d have a panic attack

 

[Hawthorn37]

Ours drops enough in the day so that in the evening the lights don’t work. It doesn’t autocorrect though. A van we hired in 2021 did auto correct at night, and it was a noticeable sound. We reported the sagging and lack of auto correct at a service during late 2024, but the dealer said VW won’t sanction any work, not even looking into the auto correct function, unless it drops 20cm

 

[sidepod]

I had a dig around in VCDS yesterday but found nothing conclusive. All I did manage to confirm is, by monitoring live data, the roof sensor switching does coincide with lights switching off. Nothing new.

 

[jaydisc]

Ours drops enough in the day so that in the evening the lights don’t work. It doesn’t autocorrect though. A van we hired in 2021 did auto correct at night, and it was a noticeable sound. We reported the sagging and lack of auto correct at a service during late 2024, but the dealer said VW won’t sanction any work, not even looking into the auto correct function, unless it drops 20cm

I think presenting that the lighting stops working would be a good avenue to pursue if you can't show the 20cm.

 

[vbk1975]

Did you happen to note how far it had sagged when the auto-correct operated?
For example, had the upstairs lights stopped working due to sag?

I’m trying to ascertain what the software uses to determine roof movement. Either failed roof lighting or ram position sensors. It may well be the same thing, the sensors deactivating the lighting?

@sidepod - I think something that is potentially an interesting difference between the T5/T6 and T6.1 control is the fact the T6.1 system doesn't appear to have an form of current sensing on the roof motor, it is purely two relays (to form an H-Bridge).

I think this is a bit of an interesting omission vs the T5/T6 setup. So the T6.1 must be driving the pump purely based on some form of timer to drive the pump rather than seeing the pump current rise as it drives the system to full pressure and starts to push fluid past the check valves.

So it could be the roof is being driven up but actually not always getting to full pressure before the pump is switched off in some instances or vehicles (esp if air in system) - it might be the time is much longer than T5/T6 normally takes, so it actually drives against the check valves for longer, but not having the sensor clearly means that whatever they do on T5/T6 they can't completely replicate on T6.1.

 

[gbtn]

A friend succeeded to change the pump under warrantly.
The issue has been fixed. I'm pretty sure that there is failed batch on T6.1

 

[Up10]

A friend succeeded to change the pump under warrantly.
The issue has been fixed. I'm pretty sure that there is failed batch on T6.1

Our experience too. We had the pump changed under warranty and it seems to have resolved the issue. T6.1 MY2024 Q1