Its a check engine light need to get the code(s) scanned when light is on, sometimes it goes off and will not set a code, so get it scanned while light is on. May be any possible cause that the computer is sensing from one of its sensors, does not mean a sensor is bad but a sensor detects an issue, I would check oil and fluid levels too.
If the car is still driving,handling and braking normally then id say yes and recommend you have the codes read and written down, alot of larger auto parts stores will do it free of charge
Yes you can drive the car, but be aware that it may go into low power mode and that will restrict your speed down to about 30mph, it all depends on what system are causing the wrench light.
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