My 2000 lincoln ls heater is still not working after i changed the thermostat and water pump,and blowing cool air out. what can it be?

SOURCE: 2000 Lincoln Ls Heater blowing cool air

You also could have air in your coolant system. You can't just add coolant on these models after you drain the system or let it run low on coolant. The degas bottles on these models also have a flaw, where they crack along a seam. Sometimes coolant will leak, sometimes not, depending on how high the crack is on the bottle. But what it is guaranteed to do is allow air into your system, which can cause havoc with overheating (air surrounds the thermostat so it doesn't open) and keep coolant from flowing, particularly through the highest point in the system: the heater core. There is a heater core bleeder valve attached to a line near the top of the degas bottle (next to the expension line up top) with a plastic, flathead srewdriver face. Turn the heat on high and run the system at idle for 5 minutes. Then open the valve and keep it open until a steady stream of coolant comes out. (It's like bleeding your brakes.) That will clear any air from the system and at least give you peace of mind that this is not your problem. Then run the motor at 2000 rpms, with the heat still on high, for about 5 minutes or until hot air starts coming out. Release the bleeder valve again until a steady stream comes out. Then let the system cool and check your coolant level and fill as needed. I'd pull the degas bottle and inspect it...should have been a recall.

SOURCE: I have a 2000 lincoln ls. the heater blows cool

ya me to, replaced therm, havent flushed core yet any known issue

SOURCE: 2000 lincoln LS AC blowing hot air i've replaced t...

You need a scanner to diagnose,not a code reader.

The DATC Module ( Dual Automatic Temperature Control Module) is a possible