2004 Mercury Grand Marquis electrical system problems
40 owner complaints filed with NHTSA name the electrical system on the 2004 Mercury Grand Marquis — 12% of all complaints for this model year.
What owners report
“The contact owns a 2004 Mercury Grand Marquis. The contact stated that while the vehicle was parked, the key fob became inoperable. The contact was not able to start the vehicle with the security warning light illuminated. The dealer was not contacted. The vehicle was not diagnosed or repaired. The…”
filed Aug 4, 2025
“Catalytic converter FAIL, engine idles rough while in park. HIGH Loss of engine power while driving Differentials in back tires are imbalanced…timing FAIL. Steering not calibrated, drivetrain out of sync altogether. Back wheels, left and right; randomly spin & torque hard while car is already in…”
filed Aug 7, 2021
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Related service bulletins
Summary to be provided on a future date.
ASI-45182 · Service Bulletin/Repair Instructions · issued Jun 1, 2015
Electrical System problems in other Grand Marquis years
| Year | Reports | Share |
|---|---|---|
| 2010 Grand Marquis | 3 | 13% |
| 2009 Grand Marquis | 4 | 15% |
| 2008 Grand Marquis | 9 | 12% |
| 2007 Grand Marquis | 1 | 1% |
| 2006 Grand Marquis | 8 | 6% |
| 2005 Grand Marquis | 75 | 15% |
| 2003 Grand Marquis | 51 | 14% |
| 2002 Grand Marquis | 10 | 13% |
| 2001 Grand Marquis | 13 | 8% |
| 2000 Grand Marquis | 17 | 10% |
| 1999 Grand Marquis | 15 | 9% |
| 1998 Grand Marquis | 15 | 10% |
Other reported problem areas on the 2004 Mercury Grand Marquis
Counts are unique NHTSA complaints naming this component group. Complaints are unverified owner reports; mileage is computed only from complaints that included a usable odometer reading.