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LTC2984 always returns the following for temperature measurements 0xFF 0xF0 0x64 0x00

I am using the LTC2984 with the Experimenter Board 2210A. I am using a diode for cold junction measurement: MMBT3904. With a type K thermocouple. I am unable to use the diode in either single ended or differential. I have used the same setup code for the cold junction diode as is shown in the Linduino application code and the application notes in the datasheet. I always get a 0xFF returned for the status of the channel when i read the data. Can you provide the proper cold junction configuration for this BJT i am currently using the following: 


  uint32_t channel_assignment_data =
    SENSOR_TYPE__OFF_CHIP_DIODE                    |
    // DIODE_DIFFERENTIAL                             |
    DIODE_SINGLE_ENDED                             |
    DIODE_NUM_READINGS__3                          |
    DIODE_AVERAGING_ON                             |
    // DIODE_CURRENT__80UA_320UA_640UA                |
    DIODE_CURRENT__20UA_80UA_160UA                |
    (uint32_t) 0x00000 << DIODE_IDEALITY_FACTOR_LSB;   // 1.003 Default
I have tried both single ended and differential but I get the same result.