1.8 Sonic Thermostat Heater + Fan Speed

[Y3llowCav]

The wife's 1.8AT 2012 sonic threw a couple codes, P0597 and P0598, for the thermostat heater circuit. Obviously the thermostat assembly needs to be replaced(again). But it seems that it's still working fine as the actual thermostat is mechanical, not electronic. There are no leaks. The ECT also seems to be reading fine on the scanner. The only adverse effect that I noticed is that the fan runs at 100% constantly regardless of coolant temperature. Does anyone have more information on why this might be and how to stop it from doing that until I can replace the part? I'm also curious what the point of the thermostat heater is if the actual thermostat is mechanical? Is it to open the thermostat sooner? Maybe something to do with the ECT reading? Thanks in advance for any and all information.

[tunerpro]

Certain diagnostic faults will cause a remedial action of commanding the cooling fan to 100%. If you unplug the MAF, the same thing happens, oddly enough.

Unless the editor allows you to disable the diagnostic entirely (not just disabling the DTC), there's nothing you can do to prevent this from happening until you get the issue fixed.

[Y3llowCav]

Sigh, that's kind of what I thought. There's nothing in the tunable parameters that pertains to this, so I'm definitely out of luck. Thanks for confirming.

[07GTS]

ive removed the electronic thermostat control in mine and fitted a lower mechanical stat, just disabled the code for thermostat control and operates like normal, find the codes in dtc's and tell it to no error report ? and it will stop the fans running all the time