2004 Mercury Sable Problems

What owners report

Owners of this 2004 Mercury Sable most often describe the car accelerating on its own, including while braking or idling, and some complaints link this to a stuck throttle or speed control cable. A second group describes brake light switch faults, with brake lights that stay on or do not work and the shift lever locked in park. Transmission failures that cause a sudden loss of drive form a third group, and some complaints describe seat back or seat belt failures.

1. 1
   Vehicle speed control

   Sudden acceleration, including when braking

   • 16 complaints (31%)
   • median 79,397 mi at 9.3 yrs old (16 state mileage)
   • filed 2012–2017

   Owners describe the car speeding up on its own, with engine speed rising even though the accelerator pedal is not pressed, often at low to moderate speed or while braking. Some complaints link the problem to a stuck throttle or a broken speed control cable, and dealers reportedly found a fractured or failed cable in some cases. Other complaints say the engine kept revving after the car was put in park or neutral, and that tapping the accelerator sometimes brought speed back to normal. Some complaints say a mechanic could not reproduce the problem, while others describe near misses and a car towed from the road. Mileage given in these complaints ranges from very low odometer readings to about 198,000 miles, and most fall between about 54,000 and 176,000 miles.

   What to check: Ask whether the speed control or cruise control cable has been inspected or replaced. In a safe, empty area, check that engine speed drops normally when the pedal is released and when the brake is applied.

   2 excerpts from owner complaints in NHTSA records

   “My Mercury Sable 2004 began accelerating on its own. The first time I was cruising at 35mph and had trouble stopping at a stop sign. Braking caused a vibration the RPM's were not going down. Driving further I noted the car would accelerate by itself. Tapping the the gas pedal quickly sometimes caused the RPM's to go back to normal. I took the vehicle to a local garage and had the throttle (cables, etc) checked. All were reported ok. The issue has happened off and on but yesterday (11/28/12) was the worst. …”

   NHTSA complaint #10486444, filed 2012-11, 99,500 miles

   “I received a panicked phone call from my 16 year old daughter after a life threatening experience. She was driving at 35 MPH when the car began to accelerate on it's own, the engine raced to 4,000 RPM and stayed there, while she frantically pressed the brake. Thankfully she was able to contain control of the vehicle as she pulled off it the road. She immediately turned off the engine, after waiting a few minutes she started the car, again it raced to 4,000 RPM. After trying this multiple times I had the car towed home. …”

   NHTSA complaint #10553933, filed 2013-11, 54,296 miles
2. 2
   Brakes

   Brake lights fail or stay on, shifter locks in park

   • 8 complaints (15%)
   • median 92,500 mi at 11.2 yrs old (8 state mileage, few)
   • filed 2008–2020

   Owners describe brake lights that do not come on when the pedal is pressed, or that stay on all the time, and some say the shift lever could not be moved out of park. Some complaints describe a workaround to leave park, such as turning the key to the first position and pressing the brake, or using the parking brake and then shifting to neutral. Owners often link these symptoms to a failed brake light switch, and some note that a recall covered earlier model years but not this 2004 model. In some cases the dealer replaced the stop lamp switch and the repair was completed. Mileage given in these complaints ranges from about 28,100 to 172,000 miles, and many reports come from cars near 90,000 to 100,000 miles.

   What to check: Ask whether the brake light switch has been replaced, and confirm that the brake lights switch on and off with the pedal. In a safe place, check that the shift lever leaves park normally when the brake is pressed.

   2 excerpts from owner complaints in NHTSA records

   “I have a 2004 Sable and the brake lights will not go off. I've tried changing the fuse to no avail. After researching, it seems that the 2000-2003 ford taurus and Mercury sables had recalls for faulty brake light switches. It appears that this is still a problem in the 2004 model!”

   NHTSA complaint #10215404, filed 2008-01, 34,000 miles

   “The brake light switch failed causing inability to get shift lever out of park mode. Brake lights stay on all the time or not come on at all. The problem was noted after parking in our garage and noticing the brake lights being on all the time. I discovered that turning the ignition switch to first indent that the shift lever can be placed in the neutral mode so engine can be started. In driving the car, the brake lights do not work. …”

   NHTSA complaint #10918494, filed 2016-10, 28,100 miles
3. 3
   Transmission and drivetrain

   Sudden loss of drive from transmission failure

   • 12 complaints (23%)
   • median 58,000 mi at 8.0 yrs old (11 state mileage)
   • filed 2004–2014

   Owners describe the car suddenly stopping or refusing to move, sometimes while driving at highway speed and in some cases with no warning lights. Some complaints describe slipping when reverse is engaged with a warm transmission, or a loss of both forward and reverse gears. Dealers or independent shops reportedly diagnosed the transmission as failed and recommended replacement, and in some complaints the car was towed. A complaint says the manufacturer would only handle the repair at the full cost of a rebuild or replacement, since the warranty had ended. Mileage given in these complaints ranges from about 18,500 to 155,000 miles, and most fall between about 52,000 and 61,000 miles.

   1 related service bulletin

   What to check: Ask whether the 4F50N transaxle bulletin on upshift problems has been checked, and whether the fluid level and any leaks were inspected. On a test drive, check for normal engagement in drive and reverse, and for slipping when the transmission is warm.

   2 excerpts from owner complaints in NHTSA records

   “While driving home at 11pm on september 2, 2006 my car stopped moving as I was making a left-hand turn. The engine was running, the electrical system was in order; the car simply would not move. Luckily, I was able to coast across the road and stop the car in a safe location. As I live in a rural area, the road was empty or I could have been seriously injured. I walked to a nearby bar where I called aaa to come and tow the car. …”

   NHTSA complaint #10195093, filed 2007-07, 52,548 miles

   “Without warning I experienced a loss of power with my 2004 Mercury Sable. After driving my car approximately 46 miles (I live 47 miles from job) I came to a stop sign and when I went to proceed through the stop sign, I was not able to do so. I had lost forward and reverse gears and the car would not move. There were no warning signs. No slipping, no banging, no grinding or any other noises that almost always are associated with transmission failure. …”

   NHTSA complaint #10454443, filed 2012-04, 61,000 miles
4. 4
   Seats

   Seat back or seat belt failure

   • 5 complaints (10%)
   • median 73,000 mi at 4.8 yrs old (4 state mileage, few)
   • 2 mention a crash, fire or injury
   • filed 2004–2014

   Owners describe a seat back that broke or a driver seat that fell backward in rear-end collisions, leaving an occupant injured. Other complaints describe a driver seat belt that unlatches while the car is moving, even after a click is heard, and a front passenger seat belt whose internal cable fractured and made the belt inoperable. In some cases the dealer did not repair the belt, and a complaint says the dealership tried to charge the owner for the replacement. Mileage given in these complaints ranges from about 20,000 to 178,000 miles, and the seat-back complaints come from cars with lower mileage.

   What to check: Check that each seat locks firmly in every position, and that each seat belt latches with a firm click and retracts smoothly. Ask whether any seat or seat belt repairs appear in the service history.

   2 excerpts from owner complaints in NHTSA records

   “The driver side, three point seat belt assembly comes unlatched while the vehicle is in motion. This is even after the belt tongue is in place, you hear a click from the latch closing and locking and the belt has been pulled on to test the connection. I took it to the dealership today and the attendant said that the seat belt latch was likely not working due to normal wear and tear. The vehicle is 10 years old and has less than 200,000 miles and is very much still drivable. …”

   NHTSA complaint #10660094, filed 2014-11, 178,000 miles

   “Dt: consumer's vehicle was rear ended. Wife was in passenger seat, and the seat back broke of bucket on left of seat, causing wife to turn slightly toward the driver.”

   NHTSA complaint #10124890, filed 2005-06, 20,000 miles

Buying note. Unintended acceleration, brake light switch, and transmission complaints are the main themes for this model year, so a test drive that checks throttle return, brake light operation, and smooth shifting in and out of park is a practical starting point. Asking whether the speed control cable and the brake light switch have been inspected or replaced, and whether the transmission bulletin was applied, can help a buyer judge the service history.

Summary written with AI from a sample of 51 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.