Firstly, thanks to this forum for helping me save hundreds of dollars. After disconnecting the battery for a transmission rebuild, i had no 4x4. The rear tires slid out and there were no lights when trying to switch to 4x4 H and L. When i first turned on the ignition, 4x4L would flash for a second. The dealer wanted $100 for diagnosis + $500 for parts + labor. Thanks to this forum and Rock Auto, i replaced it for under $200 myself in less than 10 minutes. This post is to consolidate the process and provide some pictures (unfortunately i cannot post attachments). 1) Do a couple easy checks first to save some money. Check the fuses and relays. The diagrams are here: http://www.explorerforum.com/forums/showthread.php?t=107270 (This doesn't necessarily mean that the control module is flawed so you will have to decide if you want to take the risk of going straight to the contol module. Other problems can be speed sensors, broken wires or the motor. Since the control module seems to be the most common problem, i took the gamble.) 2) Order your part. I used Rock Auto but here are some other dealers found in this forum: http://www.rockauto.com/ http://fastpartsnetwork.com/ http://www.millenniumford.com/ http://www.trademotion.com/ It can be known as a shift control module or 4x4 control module or modulator. The Ford part is TM153 and the alternate part number is 1L2Z7E453A (as of 2012). Some of the web sites will ask for a VIN number to double-check the part number. (Being from Canada, i usually use Fed Ex because they have an inhouse brokerage. Sometimes, you will get long delays because of clearing customs relying on external brokerages.) 3) To gain access, you need to swing the glove compartment to the floor. There is a plastic tab on each side that you need to push inwards. Removal of the glove compartment is not necessary. 4) The module is located in the left-centre. (It is not the one on the right that says Bosch.) From the under the dash, unscrew the single screw that holds the silver-coloured bracket in place. (Getting the two screws directly attached to the module is almost impossible). You need a 7mm socket. The other side of the bracket is not screwed and simply slides out when you pull it. 5) Turn off your ignition. (I did not disconnect the battery terminal but have read some threads that recommend it. I suspect that might be what wrecked my module in the first place.) Unplug the two wiring harnesses. Remember to use your thumb to press in the tab. I used a flat screw driver to help pry the harness off. 6) Remove the module and brakcet. Unscrew the module from the bracket. There are 2 screws. 7) Installation is the reverse. 8) Test out your 4x4 afterwards.