My question is: are the audio output (+ve) speaker wires fused anywhere? Or has anyone come across a reason why the wire would suddenly lose its continuity between radio unit and door speaker. Also does have anybody have a wiring diagram of the cabling route so I can check connectors etc.

Reason: My driver’s door speaker stopped working suddenly a weak or two ago. I assumed it was the speaker itself so bought a pair of replacement speakers. Went to change it yesterday and the new speaker did not work when plugged in. Glad I checked before drilling out the old one 😊 – therefore assumed it was the radio head itself ☹ However with trying to identify the fault I used a short bits of wires and connected the new speak temporarily to the back of the radio unit on the front right output, and the temp speaker worked. This proved that the radio output is working. I then belled out the wires from the back of the radio to the door speaker and noticed that the Front Right Positive wire does not have continuity between the back of radio unit and door speaker, whereas the front right negative does have continuity. I then used a temporary bit of wire and connected between the (+RF) on the back of the radio and the + on the actual door speaker and it works just fine. Checked the fader and balance settings and proved I have audio on all 4 speakers. So, back to my question: are the positive speaker wires fused anywhere? Or has anyone come across a reason why the wire would suddenly lose its continuity. Also does have any body have a wiring diagram of the cabling route so I can check connectors etc.

Sounds like the door loom has a broken wire in the rubber gator between door jam and a pillar, well known design fault on Superb 2 and other similar vintage VAG cars, plenty of other threads in forum with more details.  Happened on my 63 plate car at start of March and was booked in for new loom but appointment was cancelled thanks to lockdown.  Just booked in again for end of next week now that local stealer has reopened.  You can try and repair individual wires inside the gator but concensus is that other wires will likely be on their way out as well which was why I decided on the new loom rather that risk the door failing to unlock one day!

@DrCorbyLee many thanks for the reply, i will take a closer look at the gator and see if i can identify the cause there.  Will let you know my findings 🙂

Hi @DrCorbyLee  the fault definitely lies within rubber gator. in fact there are several broken wires and nearly all of them have damaged / cracked insulation exposing the copper wires. See attached photo. Certainly not going to be able to fix that with some inline crimps and insulating tape ☹️. Looks like I will also be having to get the wiring loom replaced as well. Would be interested to know what they have quoted you for replacing the wiring loom? but understand if you down want to post it here.   but thanks for pointing me in the right direction - much appreciated 🙂

No problem with pointing you in the right direction, it's only thanks to the forum that I knew what the problem was when it happened to me so happy to pass on the group knowledge.

 

The multiple damaged wires certainly ties in with other's experience, I suspect mine is similar but never managed to disconnect the gator (hands like shovels!).  You'd never notice if say the wire to the tweeter by door handle had failed or the likely intermittent connections you are getting to other switches etc in the door,, it's only when something obvious fails continuously like central locking or, in our case, main speaker that you realise there is an issue.  I thought I'd gone deaf in one ear when it happened  when I closed the door at start of 3-1/2 hour drive up from London!

 

I've been quoted £236.09 plus diagnostic charge (I've already told them that I they try and charge that II will be charging them for my time then as already diagnosed the problem for them thanks to this forum :-)  I'm guessing the split is likely 100 quid for hour's labour and the rest is the loom.  There is a new design door looms have more slack in them so should be a one off fix for the life of the car, at least until the next door or tailgate loom goes the same way!!

 

Given you have already managed to disconnect the gator end and accessed the door internals it sounds like you have the skills to do this yourself (which I don't - used to build and maintain rally cars 30 years ago but technology has moved on a little bit since then and I haven't ;-).  This provides some further useful information:

Sounds easy enough once you have gained access with just one awkward connection that is OK if you invest a few quid in the proper VW connector tool.

 

Best of luck whichever way you choose to go.   I'll let you know once mine is hopefully sorted on Friday and can then confirm the breakout cost of just the loom (FYI, not a stock item at the dealer but based on my diagnosis they were happy to order it in ready as the Master tech agreed with my diagnosis) 

If you have the door card off and connector unclipped your as well getting a wee soldering iron , lengths of wire the correct guage and shrinkwrap and doing the job properly yourself 

Your over half way there already.

Just cut out old wire and replace with slightly longer wire to stop problem happening again.

Take you half an hour from there👍

Thanks everyone, having read all the comments I have decided to take the leap of faith and having found enough slack on the door loom to allow the connector to prodrude enough to comfortably work on, I have cut the connector off and will attempt to solder in a an extra length of  (6-8inches) of wires and heat shrink them for mechanical protection. Off  now to get some wire and heat shrink.. 🙂