My 2013 Highlander threw a P0128 code, was running cold and trac control wouldn’t turn on. Heater was working at this point.
I changed the thermostat out. (Had to remove serpentine belt to reach housing.) Put everything back together and ran air out of coolant line. Now the car heats to normal temp but the heater doesn’t work. Still has a P0128, but also threw a P0300 (random cylinder misfire). Also the power windows are not working.
Is there an obvious place I should be looking?
There’s probably an air bubble in the system. There may be a specific bleeding procedure.
When you replace the thermo did you make sure the jiggle pin was in the upmost position? When you bled the system you make need to rev the system. Check for your cars specific bleed procedure.
Jiggle pin was up but def need to check the bleed procedure
Second this, air in the cooling system on newer vehicles can lead to a poor idle the system actively uses the coolant temperature to determine how it should run if air is passing by the sensor it will momentarily read at a different temp.