I have f150 kingranch 2005 ...i have two problems 1)the 4*4 will not engaged regardless of the rotary elect sw postion no sound under and no light...2)the ac when i switch it on the compressor will run but the fan will not run at all speed.

The 4WD issue
Operationally vacuum holds the IWE ( Integrated Wheel Ends ) out, and once vac is removed the spring engages the IWE.

Lift and support the front of the truck so the front wheels are off the ground ( take safety precautions, chock wheels, jack stands, etc )
Key on, engage 4x4 and try to turn the front drive shaft.
If it turns it is a problem with the transfer case.
If it doesn't it is a front axle engagement problem.

- If the front drive shaft does not turn :
Shut of the truck ( still jacked up, and supported ) remove the vac lines from the IWE. The spring should push the gears in, without the vac line on.
Check the vent line ( tube that is routed into the engine compartment with nothing attached to it ), for blockages.
If the vent line is clear, and with the vac lines off the IWE should be engaged ( both front wheels locked ).
If they lock, the problem is with the IWE solenoid not shutting off vacuum to the IWEs. There is a TSB on the 2004-2006 IWE solenoids, a newer revision has been made, and used from 2007 and newer MYs.

Here is a block diagram of the IWE system


The fan issue, is this just with the AC or with the heat / vent also ?
The KR has the EATC ( Electronic Auto Temp Control ) HVAC system, so the blower motor speed is controlled by the Front blower motor speed control. This is mounted where the Blower motor resistor is located ( for the EMTC HVAC ) and could be the cause of the issue.

Try the EATC self test :
Electronic Automatic Temperature Control Module On-Demand Self-Test The EATC 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 EATC module on-demand self-test. Make sure to retrieve continuous DTCs by carrying out the Electronic Automatic Temperature Control Module - Retrieve Continuous DTCs procedure before clearing any continuous DTCs.


•The EATC 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 EATC 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°-38°C (40°-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 DEFROST buttons simultaneously and release, then press the AUTO button within 2 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 EATC 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 Electronic Automatic Temperature Control Module Diagnostic Trouble Code Index and follow the ACTION for each DTC given. See: Diagnostic Trouble Code Descriptions
•If a condition exists but no DTCs appear during the self-test, GO to Symptom Chart Condition: The EATC System Is Inoperative, Intermittent or Incorrect Operation. See: Symptom Related Diagnostic Procedures
•To exit the self-test and retain all DTCs, press any button except DEFROST. The EATC module will exit the self-test and retain all DTCs.
•To exit the self-test and clear all DTCs, press the DEFROST button. The EATC module will exit the self-test and all 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 door actuators to automatically recalibrate.
•Continuous DTCs will be deleted after 80 ignition switch ON cycles after the intermittent fault occurs.

Electronic Automatic Temperature Control Module - Retrieve Continuous DTCs
The EATC module will retrieve only continuous (intermittent and hard) 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 DEFROST buttons simultaneously and release, then press the RECIRC button within 2 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 EATC module display. Record all DTCs displayed.
•If any DTCs appear, carry out the diagnostic procedure. Refer to the Electronic Automatic Temperature Control Module Diagnostic Trouble Code Index and follow the ACTION for each DTC given. See: Diagnostic Trouble Code Descriptions
•If a condition exists but no DTCs appear, GO to Symptom Chart Condition: The EATC System Is Inoperative, Intermittent or Incorrect Operation. See: Symptom Related Diagnostic Procedures
•To exit and retain all continuous DTCs, press any button except DEFROST. The EATC module will exit the retrieved continuous DTCs mode and retain all continuous DTCs.
•To exit and clear all continuous DTCs, press the DEFROST button. The EATC 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 door actuators to automatically recalibrate.
•Continuous DTCs will be deleted after 80 ignition switch ON cycles after the intermittent fault occurs.

Electronic Automatic Temperature Control (EATC) Module and Electronic Manual Temperature Control (EMTC) Module Cold Boot Process The purpose of the cold boot process is to allow the EATC or EMTC module to re-initialize and calibrate the door actuators. To carry out the cold boot process, follow the steps below.

1.Turn the ignition switch to the OFF position.
2.Disconnect the EATC or EMTC module electrical connectors.
3.Wait one minute .
4.Connect the EATC or EMTC module electrical connectors.
5.Turn the ignition switch to the ON position.
6.Select any position except OFF on the EATC or EMTC module. The EATC or EMTC module will now initialize and calibrate the mode doors. Calibration of the mode doors will take approximately 30 seconds .