Mercury Grand Marquis owners have reported 1 problem related to ignition anti-theft immobilizer/proximity key/sender (under the electrical system category). The most recently reported issues are listed below. Also please check out the statistics and reliability analysis of Mercury Grand Marquis based on all problems reported for the Grand Marquis.
The contact owns a 2004 Mercury Grand Marquis. The contact stated that while the vehicle was parked, the contact noticed that the key fob became inoperable. The contact was not able to start up the vehicle with the security warning light illuminated. The dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 90,000.
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all problems of the 2004 Mercury Grand Marquis
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