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I had to remove and reinstall the instrument cluster (dashboard) as a part of replacing the leaking A/C evaporator core. I have a Lincoln workshop manual for my specific car (2008 MKX) and so it was easy enough to follow the instructions. After I replaced the evaporator, installed the dashboard, and connected all electrical connections and then the battery, I tried to start the car but it would not start or even crank. The anti-theft indicator in the bottom left corner of IC does not prove out, instead it just flashes rapidly. Connecting scan tool revealed that there is no communication with PCM from data link connector. Per manual, the problem with communication between DLC and PCM must be addressed first so I followed a pin point test to check resistances. The resistance between connections 6 and 14 of the data link connector should read between 54 and 66 Ohm, but I measured 120 Ohm. The next step was to measure resistance between PCM connector 175b pin #2 and DLC pin #6, as well as resistance between 175b pin#3 and DLC pin #14. Both should be very small (less than 5 Ohm) but I measured 5,000 as much, i.e. about 25 kilo Ohm. To exclude the possibility of a poor/corroded connection of the PCM harness, I found the 2 wires (WH and WH/BU) and cut them just inside of the cabin right where they come in from the outside (I can take care of soldering them later). The resistance between PCM pin#2 and the place where I cut WH/BU, as well as resistance between PCM pin#3 and WH is small, less than 5 Ohm, so there is no problem with the wire starting from PCM harness side and the wire just past the firewall. The same wires from the cut to DLC pins #6 and #14 respectively still shows about 25 kilo Ohm. I don't have the wiring diagrams (this is a separate manual I guess), so I am stuck at this point because with dashboard in place it is impossible to walk the 2 wires in question even though I removed the front seat, the bottom finish panel under the steering wheel and the actual IC (the part where odometer and the indicators are located). Did anyone experience the similar problem and can help me please? Is it possible that I don't actually have any problems with wires and connectors, but the problem is rather caused by the PATS system itself which prevents communication with PCM thus triggering the PATS no crank event. P.S. If I connect the battery then alarm is triggered, but the key (with integrated remote on the key head) turns it off. All the functions of the remote work OK, other modules are OK too, that is ABS proves out, I can roll windows, move the seats, etc. Thank you, Oleg