Hiya Folks,
This is an interesting thread, which seems to have had one or two excellent ideas and suggestions, but then died,since the problem appears to be unsolvable :-(
I have just bought a Laguna on a 51 plate, with exactly this problem. In fact, as I write this, I am still to pick it up from the dealer!
The day I bought this car, I also looked at another car, again with the same problem. It struck me as very odd that two out of the two cars for sale near me have the same faulty dash, so I have dug further still.
My local Renault dealer is fully aware of this issue, he was able to immediately interrupt my explanation with a sigh and a look to the heavens, and tell me that this is very common indeed and that it cannot be repaired without the expensive replacement fix described in this thread. Currently, the cost stands at £350 plus VAT, plus labour!
Being a somewhat lairy individual I have now taken this to Renault UK. The reply was interesting to say the least. The customer service lady took the issue away and spoke to their techies (or should that be mechies? ), who replied "I've seen loads of these and I'm sorry to say that there is no repair other than a new display panel. The error is caused when the battery is replaced while the Keycard is in the slot. This confuses the display"(ed. burns it out I guess he means?)"and causes it to revert to factory default setting with no prespect of reversal".
At face value this seems fair enough, I guess. You would never even consider replacing a battery with a normal key in the ignition turned to position II , and having the keycard in the slot is kind of the equivalent of this, I guess. I can see why Renault might not want to take responsibility for a fault which is caused by "user misuse" of the car.
But the trouble is, this issue can cause the same failure spike even when you wouldn't expect it. The car i didn't buy the other day is a prime example. Its display failed when he had to jump start the car - something you certainly cannot do without the keycard in the slot. I've not yet read the handbook, but does it specifically state that you must never try to jump start the Laguna? If not, then Renault might well be considered responsible for failing to alert their customers of the danger. In addition to this, the battery now becomes a VERY important service item. We all take great care to get out timing belts changed at the right intervals, and yet do we also take such care to get our batteries changed too? Or do we instead wait for a failure or a difficult startup before going and getting it checked? A failure to start, could well cause the spike which does £500 worth of damage, it would seem.
Sorry to have gone on a bit, but the bottom line is - I think Renault have a case to answer here. They know it goes wrong, they even know what causes it, yet they have not warned customers - or even dealers it seems - of the dangers. If this was linked to a safety issue, it would definately have been subject to a free recall, but since the display is a "comfort" issue, I guess they have decided they can get away with charging us for it.
Can we have a show of hands over this one, who has this fault and who doesn't. Is it more widespread than we realise? We can find out by phoning up the cars for sale and asking them. I might take a hunt through autotrader online and phone a few to find out. If we can post the replies here and if it shows that it is widespread, we could use that as leverage against Renault - having shown the part to be "generally faulty".
What do you guys think?