Originally posted by Rick89GTS from 4gcelica.net 4th Gen Heater QUICK FIX STEP 1: For a temporary quick fix: undo the piano-wire loop on the heater inlet located on the firewall. Push the lever all the way to the rear for heat. NOTE: Forward means to the front of the car. STEP 2: Slide down by the passenger side left footwell beside the heater. Unclip the white plastic clip that holds the heater vent control arm. Push the lever all the way forward and that will allow heat to enter the cabin. (If you don't unhook this arm, intermittent contact will cause it to default back to the cold position.) This quick fix will get you through winter but the long term fix is the soldering repair. I've re-soldered 5 HVAC panels already but it ain't that hard, you just need patience.