New to this forum! I would just like to say when you have no heat in the cabin. Dont just think its your MATRIX!! I changed mine no change!! auxcillary pump no Luck!! Coolant system flush no luck!! Hit it with a hammer no Luck!! NO CODES ON VCDS NO LUCK!! Anyway changed heater solinoid and bingo all is good!!!! Inlet clear outlet to firewall like S--T so there you have it Dont always blame MATRIX or Blocking!! I hope this helps you Guys😀.#
Regards Dave