The air positions on the climate control all work,heat,defrost and floor but there is no warm air at any location at any temp.selection.When the temp is changed up and down you can hear a creaking noise from under/behind the climate controls when you hit that certain temperature number.there also is no vacuum on the heater control valve on the gray vacuum line under the hood regardless of the temp selected.When I tied the heater control valve open there was still no warm air in the cabin.The housing of the thermostat reads 190 degrees w/ an infrared.

 

I was wrong about the water flow valve in the heater hose.there is vacuum on that solenoid when the a/c is on.Any ideas?

 

This Explorer has the electronic dual climate control.Would this have an actuator motor for the blend door or is it vacuum controlled?

 

The blend door on the 2004 Explorer is electric, not vacuum. There's a separate blend door though for driver and passenger. Are you unable to get heat on either side?

Have you checked the temperature of the heater hose on both sides of the open heater control valve to confirm you are getting flow through the valve? It would also be worth measuring the heater core outlet temperature to confirm you're getting flow through the heater core.

You might also try the below self diagnostics to see if any codes are present. These steps are copied and pasted from the factory service manual.

Dual Automatic Temperature Control Module On-demand Self-Test

The DATC module on-demand self-test will retrieve on-demand (hard fault) DTCs only, it will not retrieve continuous DTCs. Continuous DTCs can be cleared when exiting the DATC module on-demand self-test. Make sure to retrieve continuous DTCs by carrying out the Dual Automatic Temperature Control Module — Retrieve Continuous DTCs procedure before clearing any continuous DTCs.

• The DATC module on-demand self-test will not detect concerns associated with data link messages like engine coolant temperature or vehicle speed signals. A diagnostic tool must be used to retrieve these concerns.
• The DATC module on-demand self-test will detect concerns in the system control functions and will display on-demand (hard fault) DTCs for concerns that are present during the self-test. The vehicle interior temperature should be between 4°C - 38°C (40°F - 100°F) when performing the self-test. If the temperatures are not within the specified ranges, false DTCs may be displayed.
• The self-test can be initiated after cycling the ignition switch from OFF to ON. Normal operation of the climate control system stops when the self-test is activated.
• To enter the self-test press the OFF and FLOOR buttons simultaneously and release, then press the AUTO button within two seconds. The display will show a flashing blower icon for 20 seconds, after which all vacuum fluorescent segments will be displayed if there are no on-demand DTCs present. If DTCs are present the DATC module will display "00 00" and then on-demand DTCs. Record all DTCs displayed.
• If any DTCs appear during the self-test, carry out the diagnostic procedure. Refer to the Dual Automatic Temperature Control Module Diagnostic Trouble Code Index and follow the ACTION for each DTC given.
• If a condition exists but no DTCs appear during the self-test, GO to Symptom Chart Condition: The DATC System Is Inoperative, Intermittent or Incorrect Operation.
• To exit the self-test and retain all continuous DTCs, press any button except DEFROST. The DATC module will exit the self-test and retain all continuous DTCs.
• To exit the self-test and clear all continuous DTCs, press the DEFROST button. The DATC module will exit the self-test and all continuous DTCs will be cleared.
• Always exit the self-test before powering the system down (system turned OFF). Once the self-test is exited the ignition switch must remain ON for at least 30 seconds to allow the temperature blend door actuators to automatically recalibrate.
• Continuous DTCs will be deleted after 80 ignition switch ON cycles after the intermittent fault occurs.

Dual Automatic Temperature Control Module — Retrieve Continuous DTCs

The DATC module will retrieve only continuous (intermittent) DTCs when carrying out this procedure.

• Retrieval of continuous DTCs can be initiated after cycling the ignition switch from OFF to ON. Normal operation of the climate control system stops when retrieving continuous DTCs.
• To retrieve continuous DTCs press the OFF and PANEL buttons simultaneously and release, then press the AUTO button within two seconds. All vacuum fluorescent segments will be displayed if there are no continuous DTCs present. Continuous DTCs are indicated by the presence of the degrees Celsius symbol (°C) on the DATC module display. Record all DTCs displayed.
• If any DTCs appear, carry out the diagnostic procedure. Refer to the Dual Automatic Temperature Control Module Diagnostic Trouble Code Index and follow the ACTION for each DTC given.
• If a condition exists but no DTCs appear, GO to Symptom Chart Condition: The DATC System Is Inoperative, Intermittent or Incorrect Operation.
• To exit and retain all continuous DTCs, press any button except DEFROST. The DATC module will exit the retrieve continuous DTCs mode and retain all continuous DTCs.
• To exit and clear all continuous DTCs, press the DEFROST button. The DATC module will exit the retrieve continuous DTCs mode and all continuous DTCs will be cleared.
• Always exit the procedure before powering the system down (system turned OFF). Once the procedure is exited the ignition switch must remain ON for at least 30 seconds to allow the temperature blend door actuators to automatically recalibrate.
• Continuous DTCs will be deleted after 80 ignition switch ON cycles after the intermittent fault occurs.

-Rod

 

I am getting no warm air on either side.I tried to enter the test mode for the climate control but wasn't able to get into the test mode. I'll check the temp of the heater hoses again when I get home this evening.Thanks for your time and reply.

 

The heater flow vale in the heater input hose was bad.It was broken internally and stuck in the closed position although the solenoid was working.

 

Good find. That's probably about the cheapest issue you could have too. Thank you for following up with what you found the issue to be!

-Rod