I have a 1999 ford explorer that I just got. Went to turn the heat on and it is only blowing out cold ac out the defroster. I also get the same cold air out the back heater as well. I turned it to AC and it blows cold air out the Defroster and Rear only noting out the floor or vents. Does anyone have any suggestions.

 

Welcome to the forum.

For starters, do you have the manual (****) HVAC controls or the electronic controls?

Are you positive it is A/C versus just cool/cold outside air? Please confirm that the A/C compressor clutch is engaged.

Is your concern that no settings seem to blow out the floor or panel vents, or that the air never gets warm even when the temperature is set to higher (red) temps?

-Rod

 

Hello it is all electronic controls. I am pretty sure its AC it is very cold air I can confirm that latter. My big concern is there is no heat at all it never gets warm in either the front or the rear.

 

Blend door motors are known to fail, both front and rear, in the Explorer. It's possible both of yours have failed. It's also possible that the thermostat is stuck open and the coolant is never getting up to temperature during your drives. You might want to check the upper radiator hose sometime to see if it is getting hot to the touch.

There are several modes/settings of the electronic climate control that, by design, call for the A/C compressor clutch to be engaged. I'll try to check the service manual tomorrow for a description of the modes that call for A/C as well as list out the steps to enter the self diagnostics for the HVAC control.

-Rod

 

hello
Actually one of the first things I did was check the hoses they where warm but not real hot. So I ended up replacing the thermostate. I figured it was a cheep fix so I started there. It did not fix the problem

 

I also did check and the AC Clutch is Cycling.

 

Here's how to perform the self test according to the factory service manual:
Electronic Automatic Temperature Control Module Self-Test

• The EATC module self-test will not detect concerns associated with data link messages like engine coolant temperature or vehicle speed signals. A NGS tester must be used to retrieve these concerns.
• The EATC module self-test will detect concerns in the system control functions and will display hard diagnostic trouble codes (DTC) in addition to intermittent diagnostic trouble codes for concerns that occur during system operation. The vehicle interior temperature should be between 4°-32°C (40-90°F) when performing the self-test. If the temperatures are not within the specified ranges, false in-car temperature sensor DTCs will be displayed.
• The self-test can be initiated at any time. Normal operation of the system stops when the self-test is activated.
• To enter the self-test, press the OFF and FLOOR buttons simultaneously and then press the AUTOMATIC button within two seconds. The display will show a pulse tracer going around the center of the display window. The test may run as long as 30 seconds. Record all DTCs displayed.
• If any DTCs appear during the self-test, follow the diagnostics procedure given under ACTION for each DTC given.
• If a condition exists but no DTCs appear during the self-test, refer to the Symptom Chart Condition: The EATC System Is Inoperative, Intermittent or Improper Operation.
• To exit self-test and retain all intermittent DTCs, push the blue (cooler) button. The control will exit self-test, retain all intermittent diagnostic trouble codes and then turn OFF (display blank).
• To exit self-test and clear all diagnostic trouble codes, press the DEFROST button. The vacuum fluorescent display window will show 888 and all function symbols for one second. Then, the EATC control assembly will turn OFF (display blank) and all DTCs will be cleared.
• Always exit the self-test before powering the system down (system turned OFF).
• Intermittent DTCs will be deleted after 80 ignition switch ON cycles after the intermittent condition occurs.

There is a pretty long formatted table of code definitions so it wouldn't paste in nicely, but if you have any diagnostic codes reply with them and I can look them up.

Here's what's supposed to happen with each of the settings, again from the service manual:
When MAX A/C is selected:

• The air inlet duct door is at full vacuum, closing off outside air and admitting only recirculated air.
• The heater water control valve (18495) is at full vacuum, preventing hot coolant from reaching the heater core (18476).
• The panel/defrost door is at full vacuum and the floor/panel door is at no vacuum, directing airflow to the A/C registers (19893).
• Temperature control is usually set for maximum cold but because the heater water control valve is preventing hot coolant from reaching the heater core, the air cannot be heated in any temperature control position.
• Air will be picked up at the recirc opening by the blower motor (18527). With the temperature control set for maximum cold, airflow across the A/C evaporator core will be diverted past the heater core and then directed into the passenger compartment through the instrument panel A/C registers. There is also some airflow to the side window demisters.
• The A/C compressor will be enabled when MAX A/C is selected.
• The blower motor is on.

When A/C is selected:

• The air inlet duct door is set at no vacuum, blocking the recirc passage and admitting outside air.
• The heater water control valve is also at no vacuum, allowing hot coolant into the heater core.
• All other door positions are the same as described.
• Temperature setting can be changed manually.
• The A/C compressor will be enabled when A/C is selected.
• The blower motor is on.

When vent is selected:

• The air inlet duct door, with no vacuum being applied, will block recirculated air and admit outside air. From there, air flows through the system to the instrument panel A/C registers. There is also some airflow to the side window demisters.
• The heater water control valve is at no vacuum, allowing hot coolant into the heater core.
• The floor/panel door is in the no vacuum position to block airflow to the heater outlet floor duct.
• The panel/defrost door is at full vacuum, closing off airflow to the windshield defroster hose nozzle (18490).
• The temperature can be adjusted to heat the air but the air cannot be cooled below the outside temperature.
• The A/C compressor will be disabled when VENT is selected.
• The blower motor is on.

When OFF is selected:

• The A/C inlet duct door is at full vacuum, closing off outside air and admitting only recirc air.
• The heater water control valve is at full vacuum, preventing hot coolant from reaching the heater core.
• The floor/panel and panel/defrost doors are at full vacuum, closing off the passages to the A/C registers.
• The blower motor and the A/C compressor are off.

When PANEL/FLOOR is selected:

• The air inlet duct door is set at no vacuum, blocking the recirc passage and admitting outside air.
• The heater water control valve is also at no vacuum, allowing hot coolant into the heater core.
• The floor/panel airflow door is in the partial vacuum position, allowing airflow to both the A/C registers and the heater outlet floor duct.
• The panel/defrost airflow door is at full vacuum, closing off airflow to the windshield defroster hose nozzle and directing airflow to the A/C registers. There is also some airflow to the side window demisters.
• The A/C compressor will be enabled when PANEL/FLOOR is selected.
• The blower motor is on.

When FLOOR is selected:

• The air inlet duct door is in the no vacuum position, blocking recirc air and admitting outside air.
• The heater water control valve is also at no vacuum, allowing hot coolant into the heater core.
• The floor/panel airflow door is in the full vacuum position, directing all airflow to the heater outlet floor duct. There is also some airflow to the side window demisters.
• The temperature can be adjusted to mix airflowing through and around the heater core to achieve the desired temperature level.
• The panel/defrost airflow door is in the no vacuum position, blocking air circulation to the panel A/C registers.
• The A/C compressor will be disabled when FLOOR is selected.
• The blower motor is on.

When FLOOR/DEFROST is selected:

• The air inlet duct door is in the no vacuum position blocking recirc air and admitting outside air.
• The heater water control valve is also at no vacuum, allowing hot coolant into the heater core.
• The floor/panel airflow door is in the partial vacuum position, allowing airflow to both the windshield defroster hose nozzle and the heater outlet floor duct.
• The panel/defrost airflow door is in the no vacuum position, directing airflow to the windshield defroster hose nozzle. There is also some airflow to the side window demisters.
• The A/C compressor will be enabled when FLOOR/DEFROST is selected to dehumidify the air and reduce windshield fogging.
• The blower motor is on.

When DEFROST is selected:

• The air inlet duct door is in the no vacuum position, admitting outside air.
• The heater water control valve is also at no vacuum, allowing hot coolant into the heater core.
• Both the floor/panel airflow door and the panel/defrost airflow door are in the no vacuum position so that most of the incoming air is directed to the windshield defroster hose nozzle. There is also airflow to the side window demisters.
• The temperature setting will determine the amount of air that is directed through the heater core and the amount that bypasses the heater core.
• The A/C compressor will be enabled when DEFROST is selected to dehumidify the air and reduce windshield fogging.
• The blower motor is on.

-Rod

 

I just ran the test there was one code in the system its code 025.

 

The 025 self test code translates to "Blend door failure" which would be consistent with the temperature not changing as you change the temperature setting.

There are a few threads here related to fixing the blend door, both the expensive way and the non-Ford endorsed way.

-Rod

 

yeah I have seen those posts. The funny thing is after I did the test. I know have heat coming out the defroster and the rear heat as well. I still have no heat out the vents but at least its warm now

 

Usually as part of the self test it will reset the various electric doors/flaps that it activates, so it's not unheard of that things are working better after the self test. Hopefully it will work well enough that you can put off making any repairs until you are ready to.

-Rod

 

"heat" is controlled by the blend door. "direction of air" is controlled by the vacuum doors and controller. If you always have flow to the defrost , you have a vacuum leak and not stroking the controllers to get vents or floor heat. You possibly have bad O-rings in the controller / selector on the dash.

 

look at the photos of O-rings at bottom of this link.

https://www.ford-trucks.com/forums/8...e-defrost.html