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 2009 Ford Flex owners, lightly cleaned up (personal details are redacted by NHTSA).
You can be driving down the road, and all your gauges will stop working, and all the warning lights on the dash will light up. The first time this happened my wife got stuck at a gas station all the warning lights were on and the car would not start, people tried to jump it and it would not affected at all. I looked on the internet and found were someone said to beat on the passenger side floorboard, I called my wife and told her to try that, and when she did the car would start. It doesn't do it all the time, you never know when it's going to happen. We have to just stomp on the passenger floor to get everything to start working again. If I had not found this information from somebody else on the internet my wife would have been stuck about a hundred miles from home. …
The door ajar sensor malfunctions and is crazy expensive to fix. There are numerous posts and videos online of workarounds bcz it's so common but they don't seem safe since that's a safety feature and the workarounds are simply a way to trick or bypass the warning sensors since the doors are actually closed in most cases. Ford needs to take ownership of this and issue a recall. There's a tire pressure sensor failure as well.
Passenger door ajar dash light goes on and off when the door is secure and locked. Interior lights go on and off when ajar light is displayed and power locks unlock/lock at the same time. This is a serious issue at night when the interior lights go on and off the entire time when your driving blinding you as well as I have been pulled over because they thought I stole the car. While pulled over I was asked to step out of the car and when I exited the car ibecame possessed and the alarm went off and interior lights began blinking and flashing on and off. The car alarm consistently goes off at all hours of the day and night causing the battery to go dead if your not around to shut it off. This is also issue as my car can get stolen at any time if the factory alarm isn't working or I could get carjacked because the doors won't stay locked.this issue happens in park, in drive and reverse. …
Tl* the contact owns a 2009 Ford Flex. While the vehicle was stationary or while driving various speeds, the center console failed to operate. While driving approximately 50 MPH, the contact heard a bell sound and the instrument panel lighting shut off. In addition, the low tire pressure indicator illuminated without warning and the turn signals and brake lights became inoperable. The contact disconnected and reconnected the battery cable in an attempt to correct the series of failures. Hall Ford (1310 north road st, elizabeth city, north carolina 27909) was made aware of the failures and performed a series of unknown repairs. The diagnosis information was not provided. The manufacturer was not made aware of the failures. The failure mileage was 65,000. The VIN was unknown.
1#-feb 25,2015 blew the two heating hoses off back of motor while car was sitting in parking lot with gear in park, took to joe cooper Ford to have repairs done and did. 2#- on March 14,2015 @ about 0930 during a trip to texas, got caught in traffic in forth worth tex engine over heated and spewed anti-freeze from bottom of car. We replaced the thermostat and after further checking we found that the "cooling fans" did not work. Ford motor company has known of this problem since 2007. Joe cooper Ford did not bring this to our attention even thou they knew the cause and was not forth coming, nor have we heard from Ford motor company about this issue. We check the forum for Ford Flex and found that this is and on going issue since 2007 with the Ford Flex.
Tl* the contact owns a 2009 Ford Flex. While the key was in the ignition, the anti-lock warning indicator illuminated. The contact was unable to start the vehicle. The vehicle was towed to an independent mechanic to be diagnosed, but the cause of the failure was not determined. The dealer stated that the secure lock system needed to be reprogrammed by the dealer. The dealer was not contacted. The vehicle was not repaired and the failure recurred. The manufacturer was made aware of the failure and transferred the contact to NHTSA to file a complaint. The failure mileage was approximately 169,000.
Tl* the contact owns a 2009 Ford Flex. While the vehicle was parked in the driveway, smoke appeared from the hood and the vehicle spontaneously caught on fire. The contact extinguished the fire and disconnected the battery cables. The air bag warning indicator was illuminated, but the air bags did not deploy. There were no injuries and a police report was filed. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was unknown.
This is a 2009 Flex dealer demo with 1450 miles. It has died twice while driving during a test drive. The first occurrence was while in drive, in a parking lot at about 5 MPH. The engine, A/C, radio/accessory power, and all lights suddenly died. It was as if the key had been turned to "off", except that the retained accessory power and all dash/warning lights went out as well. The car re-started easily once put into neutral. The second occurrence was in reverse, backing out of a driveway at about 3 MPH. This time the engine suddenly died, and A/C turned off, but the accessory power to the radio and dash /warning lights remained on, and the security light on the dash was blinking slowly. Again, the car re-started easily. …
Tl contact owns a 2009 Ford Flex. The contact stated that there was an oil leak on the rear of the engine. The engine was removed and the leak was repaired by the dealership. The air cylinder that lifted the third row seats was defective and had to be replaced. The rear hatch opened on its own five times; the dealer realigned the door to remedy the problem. The rear main oil seal failed so it was also replaced at the dealership. The brakes failed to stop the vehicle effectively. When the vehicle was taken to the dealership, they stated that the vehicle was fine. The battery was defective and was replaced. The transmission excessively shifted into gear when down shifting, causing the vehicle to jerk and shake. The dealer stated that they could not find a problem when they inspected the vehicle. The engine made a popping noise when he accelerated from a stop. …
I purchased this vehicle in May, 2014 as a used vehicle w/warranty (powertrain). While traveling from st.louis, missouri in stop and go traffic, the car overheated. After speeding up to get out of traffic it suddenly cooled back off. Now, during this same time, the air conditioner stopped blowing cool air until we sped up to get out of traffic. After that, it didn't happen again until I was stuck in traffic. Same problem. The fans stopped working. Here recently, I was stuck in traffic and the car overheated and the check engine light came on. Only this time, when I sped up the car didn't cool down. The coolant was fine but the car still over heated. I took the car to the dealership today and was told that it is the cooling fan module and it should be replaced. Now, I've read in several different places that this is a problem with 2008-2012 Ford Flex vehicles. …
Electrical complaints in other Flex years
Frequently asked questions
How common are electrical problems on the 2009 Ford Flex?
NHTSA has 32 complaints about the electrical system of the 2009 Ford Flex, 18% of the model year's 181 complaints. The component named most often is 12v/24v/48v battery (1 mentions).
Is there a recall for 2009 Ford Flex electrical problems?
No. NHTSA lists no electrical system recall for the 2009 Ford Flex, though it has 1 recall 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 2009 Ford Flex electrical problems start?
Half of the complaints with a recorded mileage happened before about 25,000 miles, and 41% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
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.