I have a ford explorer 2003; the "service engine soon" light has been blinking for about two weeks... what could that mean?

Really that could mean a number of things from needing LOF (lube oil filter) oil change, coolant levels are low, thermostat notice if the car is overheating etc. or if the light turns red, Red Warning light indicates an immediate danger. Pull over, turn off the car immediately and assess the problem. Symptoms that usually cause red warning lights are engine over-heating, low oil pressure, transmission over-heating, low battery voltage, and brake failure. Best thing to do is to take it to a Auto shop and have them diagnose the problem, most shops have a hand held like computer that they plug into the OBII port under the dash and it will tell them the engine light code and then you can go from there...

Blinking is bad. Very bad. That means the catalyst (converter) could be damaged. Is the vehicle running poorly? Find a shop, many parts stores will do it, but get that checked. It will be less expensive now than if you wait...

Really that could mean a number of things from needing LOF (lube oil filter) oil change, coolant levels are low, thermostat notice if the car is overheating etc. or if the light turns red, Red Warning light indicates an immediate danger. Pull over, turn off the car immediately and assess the problem. Symptoms that usually cause red warning lights are engine over-heating, low oil pressure, transmission over-heating, low battery voltage, and brake failure. Best thing to do is to take it to a Auto shop and have them diagnose the problem, most shops have a hand held like computer that they plug into the OBII port under the dash and it will tell them the engine light code and then you can go from there....

Wrong!

The SES or MIL or Check Engine Light is motivated by emissions. There are lamps that are used as maintenance reminders, but this isn't that.