heater will not work

check heater core

My jeep wrangler did the same thing and I replaced everything but the heater core. I took the heater core hoses off at the firewall and hooked up a garden hose to them. I flushed out brown stuff for 10 minutes. Heater has been fine every since

Cycle water through the heater core, you wont see the same pressure coming out due to resrictions in the hearter core but it will give you a good indicatin if there is contamination inside which eventually just cause it to clog all together. Luckly u own a Jeep which has easy access to the inlet and outlet hoses.