No heat, cooling fan seems to run long after car is shut off. 2003 Jag X Type

Bad thermostat, the cooling fan relay is doing its job perfectly: it's turning the fans on at the engne control module's request, since your engine is running too hot.

Same thing happen on one 2004 X-Type. They found out that it is the antfreeze, not have enough antifreeze, because it was leaking from the pipes that lead to the radiator. The clamps on the car are not very strong, and can loosen. Check for those pipes. I bought some nice clamps that have a screw on it so you can screw it as tight as you need.

Basicly check the coolant level before you replace any thermostats or sensors, if the level is okay I'll go with a thermostat.

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