I purchased a Mid-2010 White MacBook from Experimac 2 weeks ago and ran Tech Tool Pro 9.5 tests on it and it had failed the Smart Test for the hard drive. I had them give me money back since I was replacing the drive with an SSD anyway and the rest of the unit tested ok. Now today the Battery Sensor failed with a 14 A rating. The battery itself tested ok... is the sensor on the battery itself of the logic board? I reset the SMC but still get the same results. The battery only has 79 cycles on it so must have been replaced once and is made by SMP in 2013. Still within the warranty period but irks me because they really should test their used Macs before selling them. I feel for the people who don't know how to work thru some of these errors and find out what is going on and are at the mercy of these stores. I thought they were reputable but now I am wondering.