The nPackCfg register configures the MAX17201 to the number of cells present and also for options like balance, temperature input, and others. Bits D3-D0 represent the number of cells present, and for the MAX17201 that should be 1. To correct this, write 0x0C01 to the PackCfg register, which is the shadow register location for nPackCfg. This setting will enable Fuel Gauge Die Temperature measurement, and enable battery voltage measurement channel. This is the default and should be be a good starting point. If it works it will eliminate the configuration error.