How come heater fan wont blow - 2000 Jeep Grand Cherokee

Fan not working or you would feel cool air if heater door was working. Can you hear the fan?

start with using a meter to test for power start from fan back to switches need to check harness and connectors

I would disconnect the fan connector and use contact cleaner to clean the connection. Usually corrosion. Also fan might be going bad (Common Problem).

needs to replace the heater core

When the blower works only on the high setting its usually a bad blower resistor which is right near the blower motor. now you say it would always blow high regardless of the fan speed setting that would indicate probably the climate control unit or a connector problem somewhere. finally it not working at all may be the climate control unit or connection went bad even further. it might have a blown fuse or a bad blower motor in addition to the climate control unit or connector problem .check for power and ground at the blower motor. the power is supplied from fuses and may have a relay also. the ground is supplied from the climate control unit and goes through the resistor to control the fan speed. good luck

most a/c fans are usually located into the a/c heater box assembly most vehicles are inside behind the glove box area some are in the engine compartment at the firewall .generally not to bad to fit.regards agwbk

Hello let me verify.
1 heater wont blow out warm air unless on high?
possible clogged airfilter.low on coolant or antifreeze.

2 heater wont blow any air unless on high?
Could be a bad switch low ane med do not work.

Check the heater fan resistor.It is usually under the dash on the heater box near the interior fan.Common problem and not very expensive but depending in which country you live

check your radiator coolant, thats what I did and it blows warm again

I would check your blower motor. That sounds like the problem.