Advice: Error THC_d0013_coolantHeater and THC_w0014_coolantheaterOpenShort

[Jfitts]

I am trying to troubleshoot an error code BMS_u008 and BMS_w172. I took into a SC and was told I need a new LDU, but before I do that I want to make sure everything else is working. I got a new 12 Volt battery and the alerts went away then came back a couple days later, then I swapped the coolant heater and the codes went away for a couple drives then came back, last night I openned the DC converter to check the fuse and they all checked out and didnt show blown. I put the converter back on the car and now I am getting a THC_d00013_coolantHeater alert and THC_w0114_coolantHeaterOpenShort. I had an extra coolant heater so I swapped it out to see if that would clear the alert but its still there. The BMS_u008 and BMS_w172 alerts are gone, but not sure how to find the short in the coolant heater or what to check, Any thought or ideas would be great. I

 

[Jfitts]

 

[Jfitts]

2013 Model S 85

also when I run the thermal test I get

BATTERY_HEATER: FAILURE
TEMPERATURE_SENSOR: FAILURE