I have a 1996 Mazda b2300se 2.3 and my heater is blowing cold air. My water pump, thermometer, heater control valve, heater core and my blend control actuator all are in working order. Is it possible that my blend door is stuck on the cold side and I’m going to have to replace it? It is the only thing I can think of that’s left.

 

Welcome to the forum

1995 and up Ranger of B-series do have Blend Door issues, the actuator motors failed, the most common issue

Simple test
After engine is warmed up, temp gauge 1/3 to 1/2, open hood and feel both heater hoses at the firewall both should be warm, leave hood open
In the cab set Vent control to Defrost
turn fan speed to med low
Set temp **** to COLD
Put hand up on Defrost vent and turn Temp **** to HOT
Should feel a temp change, if not actuator is bad or Blend Door post is broken
If temp changes but only gets warm for a second then gets cold again then heater core is plugged up, put fan on HIGH and temp still on HOT, go back to engine bay and feel both heater hoses, one should be cooler than the other, if not then no circulation thru heater core, need to try and flush it, have to pull the dash to change it

You can also see if blend door is moving and manually move it to HOT by cutting a flap on heater box behind glove box
Google: DIY Fix Blend Door on 96'-00' Ford Ranger

Watch the video

With key on, engine off, turn the TEMP **** back and forth and you should hear the actuator and blend door moving, if you hear "clicking" then actuator is bad

 

Thank you very much