T5.1 Power sliding door button flashing?

[DaveyT5]

Hi everyone.

New to the forum but hoping there’s someone with knowledge of the auto sliding doors here.

I have a t5.1 high line with auto sliding doors and recently the offside door power button flashes intermittently when driving as if to warn it’s open.

It sometimes fails to open then if the button is lit. I’m guessing it a fault with a micro switch on the door seal but I can’t find any sort of wiring or parts diagram to find it.

Any ideas guys?
Any help most appreciated!!!

 

[c_paul]

Did you ever find the cause of this?

I have the same problem.

It is very intermittent with nothing helpful being logged on the diagnostics.

Main stealers have been … unhelpful.

 

[VeeDubbrs]

I have this too - Help! please guys ’n’ gals.
Mine’s a 2019 T6 LWB Shuttle with lots of factory fitted goodies. I’ve added an underslung Eberspacher air heater and aux battery with Sterling B2B under the passenger seat and those of you who know about these things can imagine how cramped it is under there.
Before any mods the left power sliding door regularly had intermittent issues bouncing open when nearly shut, but this has become very infrequent, and goodness knows how this has corrected.
A new problem affects the right slider, which used always to work perfectly. Out of the blue a couple of weeks ago I noticed the amber fault light on its switch was blinking when the ‘van’ was stationary and became steady-on when the van was moving. The electric door function was totally dead, although the central locking worked normally - different circuitry I assume. I operated the door manually and tried pressing switches at fully open and various positions but still no motor noises or clicking … totally dead.
Experimenting I found that by pulling the 40A fuse (under passenger seat) and replacing it brings the door back to normal operation and no warning lights, presumably by re-setting the control module (???), but upon starting the engine the same fault returns.
Any ideas where I should look for a solution folks? Is it possible that the connectors and/or relay nest under the B2B might have been disturbed during recent investigation into another problem I had, but didn’t show up for a couple of weeks?

 

[Robert]

Can you do complete VCDS Autoscan and post it here?

 

[c_paul]

Just an update on the symptoms mine has if that will help narrow it down.

- Main stealer has run diagnostics and said nothing shows up. !!!!???!
- It randomly works / fails
- When failed, sometimes it will open but not close. Sometimes it won't open either.
- If failed and it opens but won't close, I think the ecu doesn't realise the door is open. After 30 secs (ish) it relocks the vehicle and activates the alarm. Even though the door is open.
- If I close it by pressing and holding the button on the dash, it will not power-latch so the back of the door never pulls in. I have to open it manually and close it manually to get the door completely closed.
- If I open the door manually (all the way) and close it manually, it usually fixes the problem for a while.
- It is getting worse. But still not enough to reliably take ti to a garage when it isn't working.

Any help appreciated!!

c

 

[VeeDubbrs]

Can you do complete VCDS Autoscan and post it here?

Thx Robert ... I don't have VCDS yet ... what would be an ideal one to get to give what I need without getting into serious £££?

Incidentally ... +++UPDATE+++ the day after I posted I thought 'What the hell?' and pulled the fuse again and replaced it. This time the blinking light has stayed off and is all is still normal. I'm under no illusions though - it will undoubtedly go bad again ... maybe not tomorrow but some other time. Watch this space!

I think mine is different from c-paul, but any useful info on troubleshooting these is all 'grist to the mill'

 

[Robert]

This one would be the cheapest genuine approach.

VCDS HEX-V2 Enthusiast 3VIN

Product:VCDS HEX-V2 3VIN, Manufacturer:Ross-Tech, Price:£225.00

www.ilexa.co.uk

Alternatively you could check your neighbourhood, I am sure there would be handful amount of forum members willing to help.

 

[VeeDubbrs]

This one would be the cheapest genuine approach.

VCDS HEX-V2 Enthusiast 3VIN

Product:VCDS HEX-V2 3VIN, Manufacturer:Ross-Tech, Price:£225.00

www.ilexa.co.uk

Alternatively you could check your neighbourhood, I am sure there would be handful amount of forum members willing to help.

Thx Robert ... once I'm armed and have found my way around I'll post a report.

 

[VeeDubbrs]

This one would be the cheapest genuine approach.

VCDS HEX-V2 Enthusiast 3VIN

Product:VCDS HEX-V2 3VIN, Manufacturer:Ross-Tech, Price:£225.00

www.ilexa.co.uk

Alternatively you could check your neighbourhood, I am sure there would be handful amount of forum members willing to help.

Robert, I suppose this is now defunct ... ? ... and not upgradeable ... ? Got it in 2009 for other VWs I've had. Worked for some things but never gave data under very many of the headings ... mainly revealed only fault codes and allowed me to reset warning lights. Not much real-time dynamic data as I recall.

+++UPDATE+++ on the fault ... it tripped again this morning when I operated both doors at once using the key fob. Again reset OK and has worked since. I'll try to replicate it to see if that's a common factor.

 

[PM26]

Has anyone experiencing this issue found the cause?

I have had the same symptoms for about 12-18 months, light randomly comes on and off on the dash for the left slider. It flashes when stopped. My guess is a loose connection or faulty wire somewhere in the circuit. It comes and goes when I hit bumps, etc.

Occasionally the door will fail to automatically open from the button, key, or handles. The power latching will work but the door will not then open on the motor.

I had a number of parts replaced under warranty (although not sure the entire list but I know the trap sensor and also the module / brain), but it has always come back.

I also have central locking issues which may or may not be related - but again when hitting a bump or similar my central will unlock (I have anti-hijack on so at low speeds it can be a constant lock / unlock battle). Hence my thinking for me anyway it’s wiring, since the light coming on makes me think the car thinks the door has opened, which is probably why the central locking unlocks too.

Current plan is to start doing continuity testing after studying diagrams. My issue for this however is the intermittent nature!

 

[c_paul]

Has anyone experiencing this issue found the cause?

I have had the same symptoms for about 12-18 months, light randomly comes on and off on the dash for the left slider. It flashes when stopped. My guess is a loose connection or faulty wire somewhere in the circuit. It comes and goes when I hit bumps, etc.

Occasionally the door will fail to automatically open from the button, key, or handles. The power latching will work but the door will not then open on the motor.

I had a number of parts replaced under warranty (although not sure the entire list but I know the trap sensor and also the module / brain), but it has always come back.

I also have central locking issues which may or may not be related - but again when hitting a bump or similar my central will unlock (I have anti-hijack on so at low speeds it can be a constant lock / unlock battle). Hence my thinking for me anyway it’s wiring, since the light coming on makes me think the car thinks the door has opened, which is probably why the central locking unlocks too.

Current plan is to start doing continuity testing after studying diagrams. My issue for this however is the intermittent nature!

You are describing my EXACT issue!

I have bought VCDS to help diagnose but not had much chance to do so yet.

As you say. the problem is intermittent.

My current hypothesis is damaged wiring loom / poor connection to the door control module. It is worse when it has been raining a lot so could be water ingress.

For me the problem manifests at different levels. Sometimes it wont close. Sometime it just releases the power latching but the slide motor doesn't activate. Other times it is totally dead.

Chris

 

[PM26]

You are describing my EXACT issue!

I have bought VCDS to help diagnose but not had much chance to do so yet.

As you say. the problem is intermittent.

My current hypothesis is damaged wiring loom / poor connection to the door control module. It is worse when it has been raining a lot so could be water ingress.

For me the problem manifests at different levels. Sometimes it wont close. Sometime it just releases the power latching but the slide motor doesn't activate. Other times it is totally dead.

Chris

Cheers for the info. I didn’t have much faith in vcds since it was an intermittent fault. Certainly the numerous times it’s been into the dealers they haven’t had anything on scans to help them trace.

I think I’ll start with testing connectors from under the passenger seat to the prongs in the doors. It doesn’t make sense to me that it would be those since they are a connection that breaks when the door opens anyway, but it’s the only place I can think stuff has been ‘messed with’ (towbar after delivery so wiring touched under there). It’s about the only place I can start some checks without pulling panelling off anyway.

Interestingly I have the same theory about moisture, or perhaps temperature, making it more persistent. This time of year it seems to be more frequent than in summer.

 

[c_paul]

Interesting.

The wiring loom under the passenger seat has been butchered in mine too. But I don't know why or what they did with no chance of find out.

 

[c_paul]

I am hoping to be able to see the sensor values whilst it is failing but so far I haven't had them failing whilst I can diagnose.

Something else that may be relevant (if I haven't already said), it is as if the car thinks the door is open. BUT it also doesn't realise that it is open when it won't close. I.e. if it won't open using the key fob I can open it manually. If I do this, the car shuts down, turns off the lights, enables the alarm etc. as if the door was never opened. This would imply the door contacts are shorted to a closed position.

???

 

[PM26]

I’ll be taking out all my seats next week to move some furniture so hopefully will fit in some time to do these checks as that’s as good as time as any to also rip panelling out.

Will report back any findings!

I have tried the ‘slap and pat everything’ test including bumping at the door externally and cannot get the fault to come up. That is particularly frustrating because it can come up with even just hitting a cats eye on the road. One thing I have noticed is that when the door has been working, after a normal open and shut cycle, it can be better or worse for subsequent faults - so this suggests it’s something in the door or open / closing mechanisms or catches.

 

[c_paul]

I’ll be taking out all my seats next week to move some furniture so hopefully will fit in some time to do these checks as that’s as good as time as any to also rip panelling out.

Will report back any findings!

I have tried the ‘slap and pat everything’ test including bumping at the door externally and cannot get the fault to come up. That is particularly frustrating because it can come up with even just hitting a cats eye on the road. One thing I have noticed is that when the door has been working, after a normal open and shut cycle, it can be better or worse for subsequent faults - so this suggests it’s something in the door or open / closing mechanisms or catches.

Sort of but maybe indirectly?

On mine, when it is unhappy, 90% of the time fully opening it and fully closing it (manually) fixes it. Albeit temporarily.

I wonder if it is something to do with how far the module thinks the door is open. And hitting each end stop recalibrates it.

 

[PM26]

Sort of but maybe indirectly?

On mine, when it is unhappy, 90% of the time fully opening it and fully closing it (manually) fixes it. Albeit temporarily.

I wonder if it is something to do with how far the module thinks the door is open. And hitting each end stop recalibrates it.

Funnily I had this typed ready to respond but got distracted.

It makes me think it’s not wiring and as you say just the ‘brain’ not sensing position as it should. When mine goes to fully open and then ‘breaks’ if I slide it towards close by even just a couple of inches and then bump it to full open again, it can then be closed automatically. This can take a few attempts however.

 

[c_paul]

Funnily I had this typed ready to respond but got distracted.

It makes me think it’s not wiring and as you say just the ‘brain’ not sensing position as it should. When mine goes to fully open and then ‘breaks’ if I slide it towards close by even just a couple of inches and then bump it to full open again, it can then be closed automatically. This can take a few attempts however.

Yes - mine also does that

 

[PM26]

Yes - mine also does that

Is there a way in VCDS or the likes of carista to see the door ‘positions’ in live data? It would then be a case of seeing what changes during this ‘bumping’ operation and perhaps that would start to lead down the path of where to look at in terms of wiring or hardware.

Tagging @Pauly as I suspect you may have some knowledge on this front. I know there are also other gurus but not sure who would be best to pull in for discussion!

 

[Pauly]

Its going to be tricky one to confidently diagnose

The light up dash button is obviously a door open light but it is also a fault indicator, if an error occurs with the elec door system the corresponding door button will flash to highlight this, after seeing a flashing button i would expect VCDS too log and report an error code relating to it

Im not sure what values can be extracted using vcds for door position ?
Obviously open and shut (or perceived open and shut) can be seen, the door position is measured along the top rail, the hinge part has an integral sensor (you can see the 2 small wires that connect to it with the door open) that sits vertically above the top track and moves along it, this sensor somehow wirelessly knows the track position, it could be analogue and measure all movement/positions or it could measure 'steps' and register movement at several points along the track ?
I guess you would just have to have a look with VCDS, go into the door control module and see what measuring blocks are available

Going back to the overall issue, if its a moisture issue i would check the area the control module sits in the rear of the quarter panel as its not uncommon for water to get in through the middle rail bolts, also inside the sliding door itself there is a module in that wirelessly connects to the main control module to complete the system so would also have an effect on the system (although its only powered when the door is shut so make of that what you will in relation to your issue and observations)