What is the correct way to reset a coolant sensor on a 1998 Pontiac Grand Am?

My husband took my car to a new place to get the oil changed on Friday. He left to pick me up at work which is 10 min with traffic. I got in and left right away and went to turn onto the main road. There was steam pouring out of the right side of my hood. Pulled onto the road (car behind me, couldn't back up) and pulled over immediately. Coolant was steaming out of the coolant cap area and the hood lining was soaked and dripping at this point. Went and got more coolant but light was still on. Called oil change place and they came up and checked it out. He said that mechanically thecar was fine but the sensor wasn't resetting and took the negative off the battery. Still didn't reset. I stopped in yesterday per their request and they tried for an hour and it still didn't reset. They were then going to replace the sensor at no charge to us. Now all of a sudden its not their fault and they have video evidence.. I think he's resetting it wrong and am looking to see how to do it right. Should he have taken the positive off the battery, or both?What is the correct way to reset a coolant sensor on a 1998 Pontiac Grand Am?Not sure if the grand am has the same coolant sensor or not. If there is a sensor in the Radiator like my 1997 Grand Prix, That may be the issue. Hopefully everything is ok with your motor. In Radiator sensors fail and need replacing if you unplug the sensor and light go's out there is your sign. Look for a sensor under where the top hose connects with two wires that pushes into the side of the Radiator sealed with an O ring held with a wire clip be careful that clip launches and you may never see it again. You will need to reuse the clip.What is the correct way to reset a coolant sensor on a 1998 Pontiac Grand Am?First of all if your car is overheating then it is not fine. You should have a reputable shop test your cooling system. There is a low coolant sensor that is mounted in the coolant resevoir near the bottom of the tank. What usually happens is that when the car overheats coolant is forced out of the cap. When you go to replace the lost coolant an air bubble forms near the plunger or the plunger sticks. A couple of raps with a plastic faced hammer near the electrical connnector area towards the bottom of the resevoir will dislodge any bubbles and loosen a stuck plunger. There is no reset procedure for this light.If the lamp still remains lit and the resevoir is full then you will need a new resevoir since the sensor cannot be replaced.