There are 2 owner-reported lighting complaints for the 2010 Mercury Grand Marquisin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
INTERMITTANTLY BOTH HEADLIGHTS FLICKERING. LIGHTING CONTROL MODULE (LCM) PROBLEM ?
I WAS PULLING INTO A PARKING SPACE AND HAD ALMOST COME TO A STOP WHEN THE VEHICLE SUDDENLY LURCHED FORWARD & HIT A (VACANT) STORE FRONT. I FEEL THE VEHICLE ACCEL- ERATED ON IT'S OWN AS I WAS APPLYING THE BRAKE AT THE TIME, MY FOOT DID NOT SLIP OFF OF THE BRAKE. THE VEHICLE IS EQUIPPED WITH "DRIVE BY WIRE" OR, NO CABLE IS ATTACHED TO THE THROTTLE BODY FROM THE ACCELERATOR. THE DEALER REPAIRED THE FRONT END OF THE VEHICLE AND EXTENSIVELY EXAMINED THE THROTTLE SYSTEM. NO APPARENT CAUSE WAS DETERMINED AND THEY TOLD US IT MAY NEVER HAPPEN AGAIN. WE HAVE TRADED THE VEHICLE IN SINCE REPAIRS WERE COMPLETED DUE TO LACK OF CONFIDENCE IN IT. *TR
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026