My 2005 Chevy Malibu it won't start, or even turn over. .

SOURCE: 2001 chevy malibu- when car starts cooling fans do not come on but then do

your coolant temp sensor on the engine block is probably faulty, however, keep in mind that if it really isn't all that hot outside they may not need to turn on. Once you activate the A/C the fans come on automatically since they have to cool the condensor...

If your car is not overheating do not worry about it.

SOURCE: Chevy Malibu Power Steering Problen

This can be VERY expensive I would first contact GM customer assitance the phone number should be in your owners manual.Maybe depending on your milage they will split the cost with you.I worked 20 plus years for GM and they helped alot my customers.

SOURCE: 99 Chevy Malibu running hot

Cooling system should be pressure tested to find leaks. If leak is not external, look for intake manifold gaskets leaking coolant into the cylinders. Make sure you fill at the radiator as well as the plastic reservoir. Low heat from the heater is the first sign of low engine coolant

SOURCE: 2008 chevy malibu. cannot unlock doors from dirver

Intermittent door ajar switch contacts.

SOURCE: HOW DO I FIX/REPLACE STARTER ON 1999 MALIBU?

Starter Solenoid needs to be replaced.
Remove starter and install new solenoid