Rodent damage to NOX & Oil sensors, and AdBlue injector [RESOLVED]

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We've had a great few months with our new (to us) camper conversion but now disaster has struck: parked up in London for five days and rodents have destroyed three separate parts under the chassis. The most expensive is the NOX sensor and that's been chewed so close to the end that i dont think patching together the cables is going to do the trick. I have hope that the oil sensor cables can be fixed (would also avoid having to renew the oil, which was only replaced 2k miles ago) and probably the ad blue injector too.

Van details as attached (2019 reg.) and also pics of the damage.

My questions for forum are: w

(A) what anyone's experience of patching cables is in terms of reliability versus getting the parts replaced? I'd dont have the skills or tools to do this myself so it will be going to garage. Local garage has quoted full market price for replacement parts x3 (an eye watering amount), but has said they'd fit something I'd supply, or could do the rewiring.

(B) I've seen previous comments that after-market NOX sensors arent a great option, but OEM is about £750/800 just for that one part whereas others can be bought new for about £250/300. The wiring for the NOX sensor has been chewed so close to the end that it's pretty much a stump, so I think this particular part will have to be replaced rather than even trying to patch the wires (see attached pic).

(C) What's the best way of knowing that I'm buying the correct replacement parts? Is there an authoritative source? The owner manual is useless for that and even the printed or stamped labels on the parts that have been chewed don't seem to correspond to what's listed on sale.

(D) these cables and many others under the chassis seem to be hugely vulnerable to this type of damage, but I can't see many if any products available to protect the parts (e.g. wraparound gauze or something like that): anyone aware of effective deterrents?

And in case wondering, these issues came to light due to the "check oil sensor", "check exhaust system" and "refill adblue" errors coming up on the dash. Had diagnostics done and those codes cleared (got Halfords to return and do that no-charge as they'd fitted a new battery the previous week and I assumed these new faults were 'just' down to that and the ECU not being properly recoded... unfortunately not that simple), but they popped straight back up. In trying to get to the bottom of it myself I looked underneath and saw the oil sensor hanging down, and then saw the other two chewed parts after having crawled underneath to look more closely. Gutted that the critters have done so much expensive damage in less than a week: madness.

To be clear: these faults were not showing prior to the battery replacement. The battery was replaced as the van is 5yrs old and the battery was either original or several years old and it wasn't reliable at start-up (the nice small company that I bought from covered this replacement as part of sale price).

And yes, I have fully comp insurance but from what I see online it seems insurers would try and say this level of damage wasnt done in one sitting, and usually the van is stored in a garage as per my insurance but during the past few weeks it hasn't been as I was helping a friend to relocate.

Thanks all! A long one for my first proper post, but have been gleaning lots of useful info from this forum in recent months and I'm sure answers to these questions will be useful to other users too.
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Jeez... What a nightmare.

Where abouts was it parked?

It's a common problem unfortunately, something to do with the rubber in the cables, and not just T6s but many other VAG cars too.

We live in London, and run two vans.... Thankfully so far not been a victim of this.

I've heard of various methods of protecting the cables.... Tin foil, wire wool, mint oil, lavender oil, etc etc etc.... basically stuff that the pesky rodents don't like.

And apparently squirrels and foxes like a good chew as well.
 
Residential car park in Hackney. Not super close to any shrubbery but also in a quiet area so any rodents or foxes (of which there are many around) wouldn't have particularly had anything to disturb their picnic.

There are a few tips here re deterrents: personally I'd like to fit some sort of metal gauze as a wraparound to all of the exposed cables (of which there are many!) but there doesn't seem to be anything like that on market... just some 'chilli tape' that gets some pretty bad reviews, and which wouldn't actually stop them sinking their teeth in to start with Fox / Rodent repellants
 
I'd really appreciate some advice re (A) and (B) in particular, if anyone has experience re those? What I've read is that patch-repairing cables is generally reliable where that is possible, but on the other part of it I'd really like to know if any of you have fared OK with a non-OEM Nox sensor. The price difference is really significant, but if it's going to be failing or causing error messages then obviously that wouldn't be as great a cost saving over medium to long term.

I've basically got a week or so to get this sorted out before a big trip, so any perspectives shared here would be helpful: thanks
 
I had similar to you, cables chewed through, I had just enough wire poking out from the sensor to rejoin the cables using crimps and shrink tubing. I wrapped the repair in waterproof tape and taped the cables up out of the way, that was 2 years ago and no problems since so yes if you can get someone to repair it it should last
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For repairing I'd second @jimc91 and advise crimping over soldering - there's a good reason all the stock wiring tends to to be crimped.

You can get crimp butt splices in heat shrink covers that are good for this as the heat shrink is glued so will weather seal and also mechanically join the two cable insulations. Just be aware they need a slightly different crimping tool.

It's worth investing in decent crimps (not eBay or Amazon) as it's not something you want to do twice if you can help it, but you can get a more generic crimper as you're not going to be using it every day.


This was the crimper @TallPaul_S recommended a few weeks back.


I also use a craft hot air blower for shrinking when I'm not using my soldering station one, much simpler and neater than faffing with matches or gas lighters

 
Great, thanks for the responses. It's at my local independent garage (VW specialist) and hopefully they're going to be able to repair the wires on all three. I cant really do it myself as though I've got decent DIY capability i dont have a platform to raise it and there's not enough space for me to work under it on the ground.

Once it's hopefully sorted, I've bought some wire wool, aluminium tape and also a sink-snake cable that I'm planning to cut down with tin-snips and hopefully fashion a bit of a guard from for fixing around the repaired cables before taping them out of the way as much as possible.

The garage were fairly certain this is fox damage rather than rodents. Either way, an expensive picnic!

Appreciate the tips re the crimping tool: might get myself one of those for future. I'd fitted an optical reverse sensor to my old micro camper and used crimps on that but just used pliers to cinch them and that was quite fiddly.
 
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Three gnawed parts fixed for £360 +VAT (London prices as that's where it was parked up). Warning lights all gone now and AdBlue back to saying '5000 miles'. More expensive than buying my own crimpers but am just relieved to have it sorted, as to replace the parts would have been at least three times that cost. Garage seems to have smeared grease on the replacement plastic covers to deter future nibbles. I'll incline the van on chocks at some point soon and cover as many exposed cables as I can with wirewool/aluminium foil combo, as don't want to have to shell out like this again. Thanks for the various bits of advice, guys!

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