Another roof that won't rise

Hebridean

Hebridean

VIP Member
Messages
30
Location
Outer Hebrides
Vehicle
2015 VW Ocean with the display showing ignition? on when attempting to raise the roof. Reset the display, VW diagnostics showing no errors, checked the fuses, disconnected reconnected the engine battery all to no avail. The engine and leisure batteries are new and showing 100%, with the heater and fridge working as normal. I connected up the obd2 fault reader and came across two faults showing in the Electronic central section which have never been there before. 1) Terminal 30 turn signals and brake lights and 2) Implausible signal ignition starter switch. I tried to erase them but number two won't erase which I think is linked to the turn ignition on when trying to raise the roof.

On reading through the forums I'm thinking it's a roof sensor issue and how to go about changing them which I fear is a job too far for me to contemplate. I live in the Outer Hebrides and doubt there's anyone local who is familiar with the issue who can change out the sensors so I'm thinking a mainland trip will be needed.

I've been reading about Kernow Transporters Ltd who do this fix but they're at the other end of the country! So I'd be grateful if anyone could recommend a company in Scotland that can do this work.

Many thanks.
 
2015 VW Ocean with the display showing ignition? on when attempting to raise the roof. Reset the display, VW diagnostics showing no errors, checked the fuses, disconnected reconnected the engine battery all to no avail. The engine and leisure batteries are new and showing 100%, with the heater and fridge working as normal. I connected up the obd2 fault reader and came across two faults showing in the Electronic central section which have never been there before. 1) Terminal 30 turn signals and brake lights and 2) Implausible signal ignition starter switch. I tried to erase them but number two won't erase which I think is linked to the turn ignition on when trying to raise the roof.

On reading through the forums I'm thinking it's a roof sensor issue and how to go about changing them which I fear is a job too far for me to contemplate. I live in the Outer Hebrides and doubt there's anyone local who is familiar with the issue who can change out the sensors so I'm thinking a mainland trip will be needed.

I've been reading about Kernow Transporters Ltd who do this fix but they're at the other end of the country! So I'd be grateful if anyone could recommend a company in Scotland that can do this work.

Many thanks.
Sorry, I can't help, though I feel your pain and frustration.
Hope you can get it sorted.
 
2015 VW Ocean with the display showing ignition? on when attempting to raise the roof. Reset the display, VW diagnostics showing no errors, checked the fuses, disconnected reconnected the engine battery all to no avail. The engine and leisure batteries are new and showing 100%, with the heater and fridge working as normal. I connected up the obd2 fault reader and came across two faults showing in the Electronic central section which have never been there before. 1) Terminal 30 turn signals and brake lights and 2) Implausible signal ignition starter switch. I tried to erase them but number two won't erase which I think is linked to the turn ignition on when trying to raise the roof.

On reading through the forums I'm thinking it's a roof sensor issue and how to go about changing them which I fear is a job too far for me to contemplate. I live in the Outer Hebrides and doubt there's anyone local who is familiar with the issue who can change out the sensors so I'm thinking a mainland trip will be needed.

I've been reading about Kernow Transporters Ltd who do this fix but they're at the other end of the country! So I'd be grateful if anyone could recommend a company in Scotland that can do this work.

Many thanks.
To my knowledge a problem with the Roof Sensors always shows a Control Panel Diagnostic Code 1000.
The Roof will not operate without a signal from the Ignition Circuit. This is a safety mechanism to stop inadvertent operation of the roof when the vehicle is parked.
I would suggest investigation the Ignition system and correct that fault first.

But first. See Post 14




An "Implausible Signal" error from your VW Transporter's ignition starter switch (often triggering fault codes like 00849 or 03444) usually points to a failing electrical switch, bad wiring, or a voltage drop. It can cause dashboard warning lights, sudden stalling, or a no-start condition.
For diagnostic tips on how to check wiring and the ignition system:

Here are the most common causes and how to tackle them:

1. Weak or Failing Battery
A significant voltage drop during the engine cranking process can send corrupted or "implausible" signals to the ECU. [1]
  • Action: Check your battery health and alternator output. A weak battery is a surprisingly common culprit for this error code, even if the vehicle seems to start normally.

2. Faulty Ignition Starter Switch
The electrical part of the ignition barrel (the part behind the key cylinder) is a known wear item on Transporters. If the internal contacts are worn or misaligned, the switch fails to send the correct sequence of signals to the Body Control Module (BCM) and ECU.
  • Action: Replacing this switch is relatively common and often cures the problem.

3. Corroded or Loose Wiring/Connectors
Corrosion, moisture, or a loose earth/ground connection can disrupt the signal between the ignition switch and the engine control units.
  • Action: Inspect the wiring harness and connectors leading from the ignition switch. Clean any major earthing points near the battery and check the condition of the connectors.
For more specific forum discussions regarding this error on the T6: VW T6 Forum.
 
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To my knowledge a problem with the Roof Sensors always shows a Control Panel Diagnostic Code 1000.
The Roof will not operate without a signal from the Ignition Circuit. This is a safety mechanism to stop inadvertent operation of the roof when the vehicle is parked.
I would suggest investigation the Ignition system and correct that fault first.

But first. See Post 14




An "Implausible Signal" error from your VW Transporter's ignition starter switch (often triggering fault codes like 00849 or 03444) usually points to a failing electrical switch, bad wiring, or a voltage drop. It can cause dashboard warning lights, sudden stalling, or a no-start condition.
For diagnostic tips on how to check wiring and the ignition system:

Here are the most common causes and how to tackle them:

1. Weak or Failing Battery
A significant voltage drop during the engine cranking process can send corrupted or "implausible" signals to the ECU. [1]
  • Action: Check your battery health and alternator output. A weak battery is a surprisingly common culprit for this error code, even if the vehicle seems to start normally.

2. Faulty Ignition Starter Switch
The electrical part of the ignition barrel (the part behind the key cylinder) is a known wear item on Transporters. If the internal contacts are worn or misaligned, the switch fails to send the correct sequence of signals to the Body Control Module (BCM) and ECU.
  • Action: Replacing this switch is relatively common and often cures the problem.

3. Corroded or Loose Wiring/Connectors
Corrosion, moisture, or a loose earth/ground connection can disrupt the signal between the ignition switch and the engine control units.
  • Action: Inspect the wiring harness and connectors leading from the ignition switch. Clean any major earthing points near the battery and check the condition of the connectors.
For more specific forum discussions regarding this error on the T6: VW T6 Forum.
Many thanks for your reply and I've just ordered an ignition switch which should be here in 2-3 days, and in the meantime I'm going to check a few fuses and reconnect the control panel as suggested.
 
Many thanks for your reply and I've just ordered an ignition switch which should be here in 2-3 days, and in the meantime I'm going to check a few fuses and reconnect the control panel as suggested.
SC32/SC34 Fuse 32 on fuse holder C
Fuse 34 on fuse holder C

On a T6 these are the two Ign Feeds to the control Panel. One is Ign Position the other is Ign after Immobiliser is confirmed (in normal situations this is always together unless someone uses a non programmed key (like surf key)

I can't be sure for a 2015 van.

But if it was ign switch then the base van wouldn't work, they use common signals for the camper function.
 
An update. I found a blown 5a fuse (sb35) in the boxes below the gear stick which is related to the roof wiring harness 58d and the main harness. Anyway I changed it and no luck, and I also removed the control unit disconnected and reconnected it again without any luck. I have noticed that on pressing open with the ignition on for a half second I can hear that it's about to start to lift .

Fuse box.jpg
 
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An update. I found a blown 5a fuse (sb35) in the boxes below the gear stick which is related to the roof wiring harness 58d and the main harness. Anyway I changed it and no luck so I'm going to try reconnecting the control unit next.

View attachment 149654
That is back lighting dimmer circuit and not linked to ign feeds

So on your van assuming a T5

Check SC36 and SC 30, both 5 amps - SC is the lower fuse box from the top one (SB) you have just pointed to
 
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That is back lighting dimmer circuit and not linked to ign feeds

So on your van assuming a T5

Check SC36 and SC 30, both 5 amps - SC is the lower fuse box from the top one (SB) you have just pointed to
Many thanks for your help but they're both fine. I can't think of anything else I can do other that wait for the ignition switch to arrive.
 
Many thanks for your help but they're both fine. I can't think of anything else I can do other that wait for the ignition switch to arrive.
Try bypassing the ignition switch.
 
Well after all that I now have the roof up. I seen a remark on a similar thread where someone suggested to try using the spare key which I've just done and it worked.
Many thanks to you all for your helpful suggestions, but the big question is why did swapping the key work? any ideas?
 
Well after all that I now have the roof up. I seen a remark on a similar thread where someone suggested to try using the spare key which I've just done and it worked.
Many thanks to you all for your helpful suggestions, but the big question is why did swapping the key work? any ideas?
If you go into the diagnostic menu in the control panel, you will see something called "Hardware Menu" press enter and you should see a screen that looks like this

1783961785950.png

Can you take a picture with the Ignition key out and then with the ignition on
 
If you go into the diagnostic menu in the control panel, you will see something called "Hardware Menu" press enter and you should see a screen that looks like this

View attachment 149671

Can you take a picture with the Ignition key out and then with the ignition on
Thatnk for your reply and here is three images with the first being without the key the second with the spare key that worked and the third with the faulty key.

display 1.jpg

display2.jpg

display 3.jpg
 
Thatnk for your reply and here is three images with the first being without the key the second with the spare key that worked and the third with the faulty key.

View attachment 149675

View attachment 149676

View attachment 149677
Ok so the Rood ECf (Not control panel is working)

Shift2 ED means only one Ign is being sensed.

I believe Shft2 should be AD and that this means that pin 32 on the control panel doesn't have powered sensed, on a T5 according to the circuits in this site is fuse SC36

But since i don't have the correct circuits for your MY of van, be cautious. I would put a multi meter on each of the fuses and see if you get 12v.

If your holiday is being ruined then with EXTREME caution you could bridge fuses 30 & 36, but keep both fuses in circuit, ie bridge the fuse IN not OUT

Shft1 being 80 means Aux position is working
 
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Hi, No I've never changed it, but curiously the battery in the working spare key was dead!
 
Ok so the Rood ECf (Not control panel is working)

Shift2 ED means only one Ign is being sensed.

I believe Shft2 should be AD and that this means that pin 32 on the control panel doesn't have powered sensed, on a T5 according to the circuits in this site is fuse SC36

But since i don't have the correct circuits for your MY of van, be cautious. I would put a multi meter on each of the fuses and see if you get 12v.

If your holiday is being ruined then with EXTREME caution you could bridge fuses 30 & 36, but keep both fuses in circuit, ie bridge the fuse IN not OUT

Shft1 being 80 means Aux position is working
Many thanks for that info and I'll put the multimeter on SC36 tomorrow.
 
Just checked SC36 and all's good reading 12.8v. I had left the roof up overnight and closed it a moment ago noticing that it came down a bit faster and secured shut first time. I've had trouble in the past sealing it shut taking at least two attempts.
So I'm going to get a couple of new key batteries today and see if I can get the main one working correctly.
Many thanks to you all for your invaluable assistance.
 
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