1 Cooling system
Your cooling system should be serviced regularly. This normally requires that the coolant is flushed and replaced every one to two years. Check your vehicle handbook for the recommended intervals.
Flush out the old coolant and refill with the coolant recommended by the manufacturer.
Remember to never mix coolants as this can cause corrosion, which can lead to overheating and premature engine failure.
Check all the hoses for softness and leaks.
Check the radiator cap seal for deterioration and have a good look at all the cooling system connections and components for corrosion.
One of the problems, especially with country driving, is that the radiator core gets blocked up with dead insects and debris.
2 Drive belt
Check all drive belts for cracking and deterioration (for example fan, waterpump, power-steering, air-conditioning etc).
3 Battery
Your battery should be checked for summer.
Check water levels and top up with distilled water so that the water level is just above the plate and clean the terminals.
Some batteries are sealed and can't be topped up.
4 Tyres
Check your tyre pressures when cold, (ie travelled less than 3km) as under-inflation can cause excessive tyre wear and heavy steering.
The manufacturers handbook can tell you the correct tyre pressure.
You can add 4-5 psi (30-35kpa) to each tyre to improve fuel comsumption and handling.
Examine the tyres for wear and deterioration of the sidewalls. Uneven wear indicates a steering alignment problem.
5 General
Keep your car in a clean condition, especially the windows and lights.
Glare from the sun can cause poor visibility, so use a good quality glass cleaner on the windows, both inside and out.
Check wiper blades and replace if necessary as worn blades will smear the windscreen.
Check the operation of all lights and clean the lenses.
Use sunshades when parked to protect the interior of your car and minimise heat build up.
Have the air-conditioner serviced and ready for hot weather. Air-conditioner components can deteriorate due to lack of use, especially rubber seals and o-rings. It's a good idea to run the air-conditioner once a week during the winter months to prevent seals drying out.
Finally do all the normal fluid level checks, oil, transmission fluid, washer fluid, power steering, brake fluid and clutch fluid if applicable.
Read more about car components.