Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2008 Mercury Mariner owners, lightly cleaned up (personal details are redacted by NHTSA).
My parents purchased a 2008 Mercury Mariner this last spring, and just started to notice that the electric power steering is cutting in and out. We took it to our local garage who diagnosed the problem (error code that came up was b1342-2f) and recommended we replace the steering column. Since that is a large expense ($800) I decided to do some research and called the local Ford dealer. They looked up our VIN and told me that there was a recall on the electric power steering and that the work for the recall on the power steering was already done. (Ford's recall number for this is 14s05) my question is since we are experiencing the same failure (meaning the fix didn't seem to last) is there any recourse for us to have Ford fix the problem now? Also, how long are these 'fixes' supposed to last? The date the recall was published by NHTSA is 2014-06-05, and we are only in September of 2015. …
In March 2018, I noticed the steering wheel would shake when coming to a stop sign or stop light and make a grinding sound. It continued to do this every time for a couple weeks. Then toward mid March, I was backing out of a driveway and the power steering totally went out.it stated on panel "power steering default assist." it took extreme effort to steer the wheel to the side as the steering wheel was extremely rigid. Because it is a safety hazard to drive, it has only been driven to move car in apartment parking lot. I got this vehicle in June 2017 from a car dealer with no warranty. Ford says this VIN # is not included in recall for torque problem with power steering failure. As this is a manufacturing defect and a safety hazard, I want this vehicle VIN added to recall list. If I drive it on open road, it will surely cause injury to my family. I can't even maneuver the steering wheel.
My vehicle was covered under recall 14s05 and said recall work was done in 2014 in va under the previous owner, Ford does not have record of what "step" or part of the recall was done, there are 3 parts. Less than 4 years, the recalled part, the torque sensor in the power steering assist has faulted, which leads me to believe that it wasn't replaced under the recall. Since it's been more than 12 months or 12,000 miles they are not willing to replace the said recalled part that was originally covered. The car was in drive when the assist faulted causing steering to be very difficult and had I been driving at a higher rate of speed could have potentially been accident causing. I feel that the recall work should be extended to replacing the part since it wasn't done originally under the recall or was again replaced with a faulty sensor to fault again within less than 4 years
Tl* the contact owns a 2008 Mercury Mariner. While driving 35 MPH, the steering wheel seized and the contact was unable to steer the vehicle. The contact was able to pull over to the side of the road. There were no warning indicators illuminated. The vehicle was towed to conway Ford (2393 us-501, conway, sc 29526) where it was diagnosed that the steering column lock module needed to be repaired. The vehicle was repaired. The manufacturer was not contacted. The contact referenced NHTSA campaign number: 14V284000 (steering). The failure mileage was unknown. Contact states that when vehicle was left over night in a parking garage the steering was completely out upon starting vehicle. The only way steering would work is with the help with another person turning the wheel. Contact states ignition stopped working as well and needed to be replaced.
While driving the car on a highway, the warning light chimes and displays to "safely stop vehicle". The car no longer accelerates and slows to a stop even if you don't have a shoulder to pull off to. I normally just hit my hazard lights and pull to a stop, wait a few minutes then restart the engine. This happen once a month and sometimes twice or three times in a row. If the hybrid electronics system overheats, it May shut down the powertrain, resulting in a stall-like condition, increasing the risk of a crash. There is currently a recall on this problem #14s19. Called Ford and they said my vehicle isn't a part of it even though it clearly was built in the same time and has the exact issue. Very dangerous and scary problem.
Tl* the contact owns a 2008 Mercury Mariner. While driving approximately 75 MPH, the traction control, service engine, and ABS sensor lights illuminated and an audible chime was heard. The vehicle was taken to the dealer where it was diagnosed that the steering mechanism was faulty. The steering system was reprogrammed, but the failure continued. The vehicle was taken to the dealer where it was diagnosed that the electronic power assist system was faulty. The contact was informed that the repair was previously performed in 2014 under NHTSA campaign number: 14V284000 (steering); however, the failure recurred. The manufacturer was notified of the failure. The failure mileage was 92,720.
Tl* the contact owns a 2008 Mercury Mariner. The contact stated that the power steering became inoperbale after the vehicle was cold started. The vehicle was towed to an independent mechanic who located failure code: b2278 (steering torque sensor). The dealer (koons silver spring Ford, 3111 automobile blvd #1, silver spring, md 20904, [phone]) diagnosed that a new steering column assembly and ignition housing assembly were needed. The manufacturer was not contacted. The failure mileage was 115,000.
Power steering completely failed while operating the car, posing a danger. Transmission lurches on upshift between 1 - 2 gear while accelerating. Electrical system will not charge battery and completely fails while the vehicle is in operation on the highway, posing a danger. Vehicle May or May not restart immediately.
Tl* the contact owns a 2008 Mercury Mariner. The contact stated that the ignition switch module went out and caused the vehicle to become inoperable. The vehicle was towed to barber Ford in holland, mi (640 e 8th). The manufacturer was not notified. The VIN was unknown. The failure mileage was 180,000.
Manufacturer's faulty ignition lock module wears out prematurely and vehicle often doesn't start. Caused consistent but intermittent problem for last 3 years. Research shows this is a common problem on 2008-2012 mariners, Ford escapes and 2008-2011 Ford focus, which all use the same ignition lock.
Electrical complaints in other Mariner years
Frequently asked questions
How common are electrical problems on the 2008 Mercury Mariner?
NHTSA has 27 complaints about the electrical system of the 2008 Mercury Mariner, 6% of the model year's 461 complaints. The component named most often is ignition (4 mentions).
Is there a recall for 2008 Mercury Mariner electrical problems?
No. NHTSA lists no electrical system recall for the 2008 Mercury Mariner, though it has 3 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2008 Mercury Mariner electrical problems start?
Half of the complaints with a recorded mileage happened before about 115,000 miles, and 4% before 25,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.