Two problems related to car will not start have been reported for the 2009 Mercury Mariner. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 Mercury Mariner based on all problems reported for the 2009 Mariner.
Problem started in December 2015, and got progressively worse. Engine would not start when ignition switch was turned to the start position. Had to make several attempts at it, and apply downward force on the key until the necessary contact was made. Once started it seemed to run normal. Ford dealer diagnosed the problem as a defective "ignition lock cylinder housing". They replaced it with a new one, part number 9l8z*3511*a. Engine starts normally now. Total cost to me $527. 74.
After going through a car wash, I received a warning on the dash that there was a problem and that I should find a safe place to stop. When I returned home and stopped the car it would not restart. The same thing happened on February 16,2013, again after going through a car wash. The local dealer was able to get the vehicle running, but would not say that it was repaired.
| Electrical System problems | |
| Car Will Not Start problems | |
| Software problems | |
| Anti-theft Controller problems |