Mercury Marquis owners have reported 1 problem related to brakes failed (under the service brakes category). The most recently reported issues are listed below.
While driving in bumper to bumper traffic, the vehicle's brakes failed. The pedal was extremely hard to press which resulted in a rear end collision. Suspected the brake/gas pedal raised to the same level when switch was activated, possible depressing brake and gas at the same time. (californiahighway patrol).
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all problems of the 2003 Mercury Marquis
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