1998 Jeep Wrangler not blowing hot air. Fan is blowing cold air. Suggestions?

3 posts. the blower resistor, can be bad,
see your other anon posts. it was answered, with a schematic and free manual.

Could be different problems.
The blower uses a resistor to regulate fan speed, the resistor could be faulty.
You would need to know if the radiator is full of coolant and if both heater hoses are getting hot. There may be a temp control valve in one heater hose that is not opening up to allow flow thru the heater core.

Heater blowing cold air,indicates towards low or no coolant or the coolant flow is getting obstructed or the heater core is clogged or hot to cold moving flap/ door is stuck in cold mode. There are many possibilities, that needs to be checked. Click the link below for step by step details:--- http://technoanswers.blogspot.com/2011/10/heater-blows-only-cold-air.html ---------- This should help.Thanks.Helpmech.

The damper door is located on the passenger side, next to the floor board. You can look in and see the door, kind of under the center console, under the dash. This door controls whether the Jeep blows hot or cold air.

sounds like a broken door in the hvac housing

WELL YOU NEED TO CHECK THAT THE BLENDOORS ARE WORKING BUT OPEN HOOD WHEN CAR IS WORM TO RUNING TEMP FEEL THE HEATER HOSE THEY SHOULD BE HOT IF THEY ARE ITS MOST LIKELY BLENDOOR MOTOR OR BLENDOOR BROKE. HOPE THIS HELPS

will the air flow switch from floor to the mid to defrost? if so then we have a problem with the tempature door actuator. easy to replace just in tight place. Keep me posted for more help or if this was any help thanks

How often has the coolant been changed? My only guess is that it hasn't and the hoses and the heater core are plugged up with goo and a flush is needed

This may be the AC compressor cycling switch is defective. It is located in the larger of the 2 AC lines coming from the compressor, it has a wire connector to it with 2-3 wires. To verify this is the issue jumper the connector with a small piece of wire and see if the compressor runs.

Try this disconnect the heater hoses from the heater core use a hose to backflush the core. Then reconnect and try again.