Not sure if this is engine or interior tbh but bit of an issue as its -5 this morning! Car is a 2003 C32. I have always thought that the heating has been poor on the car but never really worried. This cold snap has proved that its barely working at all. At best all I get is luke warm air after about 30mins. I've done the reset and it just leaves the 2 lights flashing, I have no clicking noise to suggest a broken valve and I can hear all the air moving about during the test. I understand this means that its logged a fault. When looking through the history I found a receipt that notes post water pump change: "unable to test heating due to heating system fault - customer aware" so sounds like its not a new thing. Any hints or tips? Bloody typical as Im trying to sell it!!!