The ASX was launched in Australia in 2010 and from the very start was offered with a CVT transmission, as well as a conventional manual transmission, depending on what specification you chose. The ASX’s CVT differs from some by having six fixed steps which makes the car feel and sound a little less alien to drive, but also potentially sacrifices a small degree of efficiency. That’s because the CVT is most efficient when allowed to use an infinite range of just-so ratios, rather than the six fixed ones Mitsubishi specified.

First things first. Your daughter’s car came with a five-year warranty. That warranty will have started when the car was first registered. So job one is to see if it’s still within that five-year/100,000km window and, if it is, make this Mitsubishi’s problem. Even if the car is slightly out of warranty, if it’s been serviced properly, you might find Mitsubishi will meet you part-way with the cost of repairs.

Beyond that, the touch-screen function has either failed or the unit has experienced a moment of electronic confusion. See if there’s a reset function for the head unit and if there is, perform the reset and see if it comes back to life. The other thing to try would be to disconnect the car’s battery for at least ten minutes and see if the screen recovers when you reconnect the battery.

This is a very common problem for owners of modern turbo-diesel cars who only do short, stop-start runs in city or suburban traffic. When the engine and exhaust can’t get hot enough for a DPF burn-off, the computer dumps extra fuel into the engine to get everything hot. If some of this excess fuel gets into the engine’s sump, it can force the level of the sump to rise, leading to the warning light you’ve just seen.

In the worst-case scenario, this fuel in the sump will dilute the lubricating oil and that can lead to a damaged engine. But as you’ve found, even if that isn’t the case, there’s still a price to pay to manually force the DPF to burn off as well as change the oil for fresh, undiluted stuff.

The solution is to make sure you drive the car for at least half an hour at freeway speeds once or twice a month. That will get things hot enough for a complete DPF burn and will keep you out of the workshop. Mind you, making this sort of effort might cost you more than the fuel savings you gain from owning a diesel car. This is just one reason a modern turbo-diesel is not ideal for every consumer.