No Heat - EATC system or Heater Core | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

No Heat - EATC system or Heater Core


February 6, 2010
Reaction score
City, State
Denver, CO
Year, Model & Trim Level
97 Explorer EB
I have a 1997 Explorer EB V6 4.0 SOHC with the EATC. Everything works on the EATC panel except the defrost, panel or floor does not blow warm/hot air when the temp setpoint is high (75-90). The thermostat works (just changed to a new 195 degF), coolant is new, system was flushed with Prestone cleaner and flush kit. The heater hoses are both (inlet and outlet) are both hot to touch after 5 minutes of idling, so the heater core is getting hot coolant flow. I see the temp coolant control valve on the lower heater hose move when switching from heat to A/C. I've witnessed the blend door move from up (A/C) to down (Heat). When running the EATC diagnostics with the key in the on position, engine off, I get a code of 024 - blend door calib.
My only idea right now is that the heater core pipe is severely coated on the inside that no heat transfer/exchange is occurring in the heater core. And that a CLR flush and forced air flush would break up the coating. Am I going down the right path here or is there something else I need to diagnose. The likely culprit might be the blend door internals that I cannot see from under the dash are broken. How do I diagnose either condition above or other conditions I am not listing. THanks.

Blend Door Actuator disconnected, making clicking noise

So I pulled out the glove box and found the electrical connector to the actuator unplugged (by the previous owner). Plugging it in, the motor made clicking sounds. I removed the motor and plugged it back in and the clicking sounds stopped and I witness rotary motion of the shaft. Is my blend door stuck? I felt the top pin of the blend door with my fingers and it fells intact, no loose pieces.
I opened the actuator cover and the plastic gears are not stripped, but the 8 feedback fingers on the big gear are covered in grease as is the PC board track that they connect with. When I plug in the actuator with the cover off, the motor drives the gear to it's end point and keeps moving, creating a clicking sound. I will put the cover back on and test it. Is the actuator the problem?