text: <s>[INST] Powerflex 70 Fault 08 on power up I just replaced a drive with one from my stock. As soon as I power up the drive I get F08 'Heat Sink Over Temp'. If I look at parameter 218 it shows -19 degree. Drive is not in a cold enviroment and the ambient temperature is about 22C. [/INST] It's a broken wire on the temperature sensor that goes back to the heat sink, or it's a failing main control board. I've had this problem on a PowerFlex 700 after it had been disassembled for repair. The wire harnesses are well built and have good latching connectors but they can still be damaged. \\n </s>