Hi all,
This is a heads up for anyone with a 9N3/Mark IV series Polo TDI. Our Polo was the 2007 face-lifted model which I think ran from 2005 to 2009 but the basic layout could be as late as 2014 and earlier than 2005?
This (initially intermittent) fault came about without warning and luckily the first time it was in a quiet suburban street but the major concern was when it happened driving across a very busy city intersection and the engine died.
After we had the cause found and fixed this is the letter I sent to VW Australia…
“I would like to bring to your attention that our Volkswagen 2007 Polo (9N) has had a serious safety fault caused by poor assembly practices in the factory.
It is extremely concerning that this fault could happen to anyone around the world in any Polo of this vintage or, perhaps, other models?
The fault was eventually determined to be the 5 amp fuse (position 17 in the fuse panel) for the ECU power supply blowing, stopping the engine instantly and without warning (like happened to my wife whilst transiting through a busy intersection).
The root cause for the fuse blowing was due to the main wiring loom (that runs between the fuse panel inside the car and the engine bay) shorting out on a bare bolt that fixes a support bracket on the firewall for the vehicle’s dashboard assembly.
We have been without the car for a number of weeks and the whole exercise has cost $1400 in labour to remove the entire dashboard, trace, find and repair the wire(s) that had been damaged.
This is an obvious oversight in the car’s assembly and could have contributed to serious injury or death.
The fact that the wire (that had been earthed) was a critical supply and was randomly damaged, given the large number of wires in the loom assembly, does not reduce the severity of the risk to other motorists. If required I can supply photos of the damaged wiring loom also showing the burn marks from the shorting out on the bolt.
I trust you will alert your service departments of this issue…”
I supplied the photos to VW Customer service.
They then passed this onto their “Technical service section”.
After a day or two I was contacted again by the Customer Service Rep. The response from the Technical service people was …”we cannot determine the cause of this fault as the repair work was not carried out by an authorised VW service centre..” or words to that effect. No further correspondence would be entered into, end of story.
What? OK. Thank you VW Australia for your concern about our safety!
Obviously, as I said above, it could have been any wire in that loom. In our case it was the ECU supply and it killed the engine without warning.
I was not asking for any money, even though it cost heaps to find this fault. The work was carried out by a very reputable VW specialist (non-factory) service business. The pedal cluster, steering column and the whole dash was removed as they traced the wiring loom to find the fault.
This is just a warning to all with this vintage Polo to be aware because VW is going to do NADA.