It's a very common problem for the insulation of the wires of the intake air temperature sensor (IAT sensor) to get damaged and peel off.
This happens not only with the IAT sensor wires, since I have seen this type of problem in the connectors of other fuel injection system sensors.
When the insulation of the cables peels off, they short-circuit to each other, causing a diagnostic trouble code (of the affected sensor) to light up the check engine light.
In the photo above (which is from an IAT sensor connector of a 2003 Ford E250) you can see this type of damage.
You can find this tutorial in Spanish here: Cables Dañados Del Conector Del Sensor IAT (at: autotecnico-online.com).
How Do You Do Repair This Type Of Problem?
There are two solutions available: 1.) Replace the connector. 2.) Repair the cables by taping them with electrical insulating tape.
The solution I prefer is to replace the connector with a new one, but this solution can be time consuming due to the fact that the connector has to be ordered online.
Wrapping cables in black electrical tape is usually the fastest solution. In addition, the cables can be mended (with electrical insulating tape) while looking for a new connector.
In the case of the connector in the photo above, I replaced it with one that I cut from a Ford engine wiring harness I had lying around. This connector could no longer be saved (repaired) with electrical insulating tape.
If this info saved the day, buy me a beer!
