The heater core is leaking. GEt a manual from DISCOUNTAUTOREPAIRMANUALS.COM and replace it.
Because your jeep wrangler is over heating, you must have a sensor in the dash not working If that smoke is steam, the heater core is leaking and in need of replacement.
What do you mean by "has no heat"? No air blowing out, blowing out cold air when heater is on, blowing nothing at all? Heater not turning on? What specifically is happening?
it could be a couple of things you could have a bad thermostat or a bad heater core
Your heater core is plugged and you need a thermostat.
Because you don't have enough coolant in your radiator.
One reason your home electric heater is blowing cold air is the heating elements are burned out. A bad thermostat may also be the problem.
Have you checked your thermostat?
It would be best to disconnect the coolant lines and flush the core after the radiator flush. This will clear any sediment from the core.
The water pump on the engine circulates coolant though the engine, radiator and heater core (which is usually located under passenger side of dash). The heater core looks like a small radiator and once the engines coolant starts warming up thr heat can be spread by the blower motor mounted to the side of the heater core. Voila! Hot air blowing out of whatever vent you choose.
check the coolant level, or, possible stuck thermostat.
Check the radiator for full coolant. Check the engines water pump and thermostat, as the engine coolant carries heat from the engine into the heater core.
It could be the heater valve which is located under the hood to the passenger side down below the radiator and fan units.