On older cars like this one, some pretty strange electrical things can start to happen as switches and wiring ages. The first thing to check for is that there’s not a cargo area or interior light staying on when it shouldn’t and subsequently flattening the battery.

But the failure of the stereo and temperature gauge both point to a body computer problem (as does the battery going flat). The body computer basically controls all the car’s functions that are not driveline related. So, the central locking, lighting, entertainment, security, power windows, climate control and much, much more are body-computer driven. And if this computer fails, lights can turn themselves on, the central locking can cycle over and over again and various other electrical bits and pieces can switch themselves on and drain the battery.

But there’s one other check to make before blaming the computer (which, on a 1994 Corolla, won’t be as complex as one on a more modern car), which is to make sure there are no bad earths on the car. Failing gauges are a common symptom of a bad earth somewhere on the car, and if that’s the case, you might find this is also causing the starting problems by not allowing the battery to fully charge when the car is driven.

If it hasn't been changed before it's long overdue, on time and on mileage. Toyota service specialists recommend changing every 100,000   km and/or five years, and the risk is too great to ignore the recommendation.

The tyres she has bought in the past are very cheap ones and I would suggest she should look at a better quality tyre, such as a Michelin the next time if she wants better mileage. She could also have the alignment checked to make sure all is in order in that area as well.