Q: After replacing the ECM in a 2002 Mercury Mountaineer what will be the reason for it not to fire or start

asked by on March 09, 2018

After replacing a ECM module my car will not fire or start what could be the issue

My car has 1010800 miles.
My car has an automatic transmission.

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On cars built after the late 1990’s, replacing an ECU is a much bigger deal than just plugging in a new box. The ECU has to recognize the serial number of the car and the other modules in the car. The reason for this is to prevent chop shops from stealing cars, taking them apart, and selling off the modules to the repair industry. Replacement modules whether new or used must be programmed with the VIN before they will operate. This requires specialized scanning equipment. To get this done, you can contact YourMechanic. They can send a technician to your home or office to check out your Mountaineer and let you know what it is going to take.

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