This TSB provides a procedure to diagnose and replace, if necessary, an automatic transmission with Incorrect Ratio DTC (transmission clutch slip in gear above limit) listed on Page 2.
full bulletin at NHTSA ↗2012 Hyundai Sonata powertrain problems
severe Owners of the 2012 Hyundai Sonata have filed 93 NHTSA complaints about the powertrain, typically surfacing around 88,000 miles at roughly $2,500 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See powertrain across all vehicles →
Failure mileage
Complaints
93
Recalls
0
Avg fix
$2,500
| Model year | powertrain complaints |
|---|---|
| 2008 Sonata | 14 |
| 2009 Sonata | 40 |
| 2010 Sonata | 19 |
| 2011 Sonata | 144 |
| 2012 Sonata (this page) | 93 |
| 2013 Sonata | 83 |
| 2014 Sonata | 51 |
| 2015 Sonata | 125 |
| 2016 Sonata | 58 |
8crashes
2fires
6injuries
What stands out
Owners have filed 93 powertrain complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
Among the 20 model years of Hyundai Sonata in our records for powertrain problems, this one ranks #3 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering powertrain on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
Hyundai has launched an anti-theft software upgrade and window decal campaign (Campaign 993), combined with an anti-theft steering wheel lock campaign (Campaign P32), in response to an increase in thefts of certain 2011-2022MY Hyundai vehicles not equipped with engine immobilizers targeted through social media. For certain vehicles that cannot be updated with the software (Campaign 993), Hyundai is offering customers steering wheel locks at the dealer (Campaign P32). This Dealer Best Practices Guide provides information to assist dealership personnel with customer questions relating to the immobilizer software upgrade, window decals and steering wheel lock ant-theft solutions available from
full bulletin at NHTSA ↗If you are servicing an applicable vehicle with the following symptoms and DTC, follow the Service Procedure on Page 4. ï· Check Engine light on ï· DTC P0880/P088000 - TCM Power signal error open/short ï· Transmission stuck in 4th gear fail-safe ï· Harsh shift into Reverse and Drive
full bulletin at NHTSA ↗The automatic transmission warranty repair policy authorizes in-dealership repairs of the following components for both OEM (new) and remanufactured automatic transmissions:
full bulletin at NHTSA ↗If you are servicing an applicable vehicle with a âCheck Engineâ light on and one or more of the DTC listed below, follow the repair procedure and replace the related solenoid and oil pressure harness.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report widespread transmission failures without warning, often at highway speeds. A hybrid owner reported first transmission failure at 79,672 miles and a second at 84,984 miles—both with zero warning lights. Multiple owners describe sudden loss of driving power, RPM issues preventing gear shifts, jerking and hesitation during acceleration, and complete transmission shutdowns. One owner replaced a CVT transmission only to experience the same rattle noise eight days later. Hybrid-specific problems emerge repeatedly: battery charging stuck below 50%, hesitation when quick acceleration is needed to avoid collisions, and "hybrid system warning" messages forcing owners to pull over. Engine issues compound the picture. Owners report thrown rods, complete engine seizures, and catastrophic failures at relatively low mileage (80,000–90,000 miles). Check engine lights come on intermittently or don't illuminate at all despite active failures. One owner had a short block replaced but continues experiencing lurching, fuel delivery problems, and repeated check engine codes the dealer cannot diagnose after six weeks in the shop. Other powertrain concerns include fuel rail pressure codes (P0087), oil consumption before recalls were issued, and unintended acceleration incidents. Shift cable recalls from 2014 are reappearing in later years. Park engagement failures leave vehicles rolling unexpectedly. Multiple owners report dealerships unable or unwilling to diagnose issues, clearing codes without fixing root causes, or refusing warranty work based on mileage despite the defect being long-standing.
Same Hyundai Sonata powertrain reports on nearby years: 2010 · 2011 · 2013 · 2014 · 2015
Failure modes owners describe
Transmission failure - complete loss of drive
Transmission fails without warning, leaving vehicle unable to move or accelerate. Often occurs on highways at speed, creating dangerous situations. Multiple owners report first and second transmission replacements failing at relatively low mileage.
When: 79,000–170,000 miles; can recur within weeks or months after replacement
Symptoms owners cite: Vehicle stops driving entirely; No acceleration response; Vehicle stranded on roadway; No warning lights before failure; Complete loss of motive power in traffic
Repairs/costs cited: Transmission replacement (remanufactured units reported), but failures recur; owners cite $6,000+ out-of-pocket costs when out of warranty
Recalls/TSBs owners mention: Warranty replacement on first failure (at least one owner); denial of coverage when mileage exceeds warranty limits
Transmission shifting problems - jerking and hesitation
Transmission jerks, hesitates, or refuses to shift smoothly. Occurs during normal driving and acceleration. Software updates (Service Campaign 953) reported to trigger rough operation in at least one case.
When: Various mileage; one owner noted onset after software update for knock sensor detection
Symptoms owners cite: Jerking during acceleration; Hesitation when moving from stop; RPM spikes without gear engagement; Engine racing with minimal motion; Transmission jerks worse after software updates
Repairs/costs cited: Dealership attempted ESC relay replacement; no lasting fix; owner reported costs out of pocket once warranty expired
Recalls/TSBs owners mention: Service campaigns (e.g., 953 knock sensor detection); software updates; some dealers refuse further work claiming out-of-warranty status
Transmission downshift and loss of power at highway speeds
Vehicle downshifts unexpectedly at highway speed, drastically losing velocity. Occurs in blue/eco mode without warning. Makes highway merging and passing dangerous.
When: Various mileage; one owner noted 100,000+ miles when issue began recurring
Symptoms owners cite: Sudden downshift from 6th to 4th gear or lower; Loss of highway speed without driver input; No warning lights; RPM drop and unresponsive acceleration; Issue does not occur in sport/manual shift mode
Repairs/costs cited: Dealership unable to duplicate; codes cleared but issue persists; no permanent repair offered
Recalls/TSBs owners mention: None documented; dealership diagnosis inconclusive
Hybrid battery charging and system failures
Hybrid battery refuses to charge above 50% or fails to maintain charge. Hybrid system warnings appear on display forcing vehicle to stop. Battery is not the 12V starter battery but the main hybrid battery. Loss of electric assist compromises acceleration and safety response.
When: 60,000–145,000 miles; recurring episodes months apart
Symptoms owners cite: Battery will not charge above 50%; Hybrid system warning message on dash; Loss of electric motor assist; Vehicle stranded after warning forces pullover; Inability to perform evasive maneuvers due to lack of electric reserve
Repairs/costs cited: Dealership service indicated charge levels 'normal' despite owner concerns; attempted replacement of hybrid main battery and fuses without resolution; no factory solution found
Recalls/TSBs owners mention: No documented recall or TSB; dealership claimed behavior was within spec
Engine rod knock, seizure, and premature failure
Engine throws rod or seizes completely, typically between 80,000–90,000 miles. Occurs without prior symptoms. Second engine failures follow replacement when fuel tank contamination is not addressed. Metal debris in fuel system is root cause.
When: 80,000–90,000 miles; some vehicles fail again post-replacement at similar mileage
Symptoms owners cite: Loud knocking noise from engine; Sudden loss of power while driving; Engine warning lights and burning smell; Engine stalls on highway; Complete engine seizure or rod failure
Codes mentioned: Check engine light (intermittent or persistent)
Repairs/costs cited: Short block replacement under recall; fuel tank NOT replaced, leading to repeated failures; owners cite metal debris contamination built into new cars
Recalls/TSBs owners mention: Engine replacement under recall (17V226000, 15V568000); denied full reimbursement if VIN not included in recall list; fuel tank replacement not addressed
Check engine light and fuel system faults (P0087)
Check engine light illuminates with P0087 code (fuel rail pressure low) or other codes. Multiple mechanics unable to diagnose root cause. Problem described as intermittent. Oil thickening and fuel economy degradation reported alongside.
When: Various mileage; one owner at 1,883 miles already noted poor fuel economy
Symptoms owners cite: Check engine light on; Code P0087 fuel rail pressure low; Intermittent nature prevents diagnosis; Poor fuel economy (23.73 MPG vs. expected 34–39); Oil darkening and thickening
Codes mentioned: P0087
Repairs/costs cited: Fuel pump, fuel filter, fuel pressure sensor, and fuel pump driver module replacement suggested but not verified by factory; TSB-15-01-010 may apply; one owner advised to clear code without diagnosis
Recalls/TSBs owners mention: TSB 15-01-010 references fuel system issues; dealerships reluctant to diagnose individual components
Unintended acceleration and loss of braking response
Vehicle accelerates without driver input or despite brake pedal being depressed. Occurs at low and highway speeds. Vehicle cannot be controlled. Two incidents involve crashes; one vehicle moves in bumper-car fashion (forward and reverse repeatedly).
When: Various mileage; one at 53,000 miles; one parking lot incident
Symptoms owners cite: Vehicle accelerates with foot off gas or brake applied; Cannot stop vehicle with brake; Vehicle moves in reverse unexpectedly after forward acceleration; Inability to control vehicle motion; No warning lights
Repairs/costs cited: Dealers unable to duplicate or diagnose; one owner reports vehicle crashing into pole and later sideswipe of tree
Recalls/TSBs owners mention: No documented response or recall for unintended acceleration
Hybrid acceleration hesitation and delayed response
Vehicle hesitates and de-accelerates when quick acceleration is needed to avoid collision or merge onto highway. Owner describes car 'powering down' to determine battery vs. gas mode, stalling briefly, then slowly accelerating. Dangerous during evasive driving.
When: Early in ownership (one complaint at 1,883 miles)
Symptoms owners cite: Hesitation and de-acceleration on sudden throttle input; Vehicle stalls briefly while system decides battery vs. gas mode; Slow acceleration afterward; No warning lights; Hybrid battery will not charge above 50%
Repairs/costs cited: Hyundai service stated battery charge behavior was 'normal'; no repair attempted
Recalls/TSBs owners mention: Dealership indicated charging behavior within specification
Transmission cannot shift; stuck in park or drive
Transmission becomes locked and will not shift into or out of park or drive. Control module and other components replaced but issue recurs within two weeks. Shift cable may also be involved (recall 14V434000).
When: Various mileage; one at 39,000 miles
Symptoms owners cite: Cannot shift vehicle out of park; Cannot shift into gear after parking; All dashboard lights illuminate; Vehicle will not move; Issue recurs shortly after repair
Repairs/costs cited: Control module replaced; issue reoccurred within two weeks requiring second repair; no lasting solution
Recalls/TSBs owners mention: Recall 14V434000 (Power Train) exists but does not apply to all vehicles; dealerships state some vehicles excluded from recall
Shift cable detachment or pin failure
Transmission shift cable detaches from shift lever pin, causing vehicle to appear in park while still in drive or preventing proper gear selection. Recall issued in 2014 but fix fails in subsequent years on same vehicle. Vehicle can roll unexpectedly.
When: Recall issued Sept 2014; one vehicle failed again June 2020 (after recall was performed)
Symptoms owners cite: Vehicle rolls away when parked; Vehicle appears to be in park but rolls; Shift cable detaches from shifter; Cannot engage park properly
Repairs/costs cited: Recall 14V434000 performed Sept 2014 ($974 cost to owner in 2020 when it failed again); part initially on backorder for months
Recalls/TSBs owners mention: Recall 14V434000 issued; parts availability delays (months); secondary owners denied warranty coverage; fix is not permanent
Vehicle rollaway when parked
Vehicle rolls backward or forward when parked and engine turned off, even when driver believes park is engaged. Multiple incidents result in injuries and property damage. Related to shift cable and park engagement failures.
When: Various mileage; incidents at 30,000–112,000 miles
Symptoms owners cite: Vehicle rolls backward or forward after parking; Vehicle will not stay in park on flat or sloped surfaces; Can be shifted into any gear and will roll regardless; Vehicle rolls even when parked on flat driveways
Repairs/costs cited: One owner injured with 10 stitches to chin; another dragged 20 feet and hit with injuries to head, leg, arm; property damage (tree collision, fence collision)
Recalls/TSBs owners mention: Recall 14V434000 addresses transmission shift cable; one owner denied coverage because vehicle excluded from campaign; no other manufacturer response documented
Engine oil consumption excessive and fuel tank metal contamination
Engine consumes excessive oil before and after recalls. Metal debris found in fuel tank from manufacturing contaminates replacement engine blocks. Factory fuel tank is not replaced during engine recall, so debris continues to circulate.
When: Present at purchase; continues after engine replacement
Symptoms owners cite: Rapid oil level depletion; Metal debris visible in fuel tank; Repeated engine failures post-replacement; Dark and thickened oil
Codes mentioned: Check engine light (oil pressure warning)
Repairs/costs cited: Engine block replaced under recall; fuel tank should have been replaced but was not; owner reports second engine failure due to same contamination
Recalls/TSBs owners mention: Recalls 17V226000 and 15V568000 (excessive oil consumption); engine replaced but fuel tank replacement not included; some owners denied reimbursement if VIN not in recall list
Engine stalling and knocking at low throttle response
Engine stalls or makes loud knocking/rattle noise during acceleration over 40 MPH. Noise related to metal debris and engine recall condition. Stalling occurs sporadically even after CVT replacement.
When: Throughout ownership; one vehicle had noise since purchase (Dec 2011); stalling at 45,000 miles
Symptoms owners cite: Loud rattle or knocking noise from engine during acceleration; Engine stalls unexpectedly; RPMs increase but car does not accelerate; White smoke from tailpipe; Dashboard lights blink on and off
Codes mentioned: Check engine light (blinking), Engine oil-pressure warning light
Repairs/costs cited: CVT replacement after 2 weeks; noise returned within 8 days; TSB and recall (15V-568) applied but dealership claimed no metal debris issue; multiple visits without resolution
Recalls/TSBs owners mention: Recall 15V-568 (engine-related); CVT replacement; Service Campaign 953 (knock sensor detection system); no permanent fix achieved
Engine fire and underhood fire
Engine compartment fire occurs. One vehicle caught fire from the exhaust manifold area after dealership service. Fire consumption destroyed front engine area completely.
When: After dealership service (vehicle in shop for 1.5 months prior)
Symptoms owners cite: Fire shoots out from exhaust manifold area; Vehicle burns completely in front engine area
Repairs/costs cited: Vehicle total loss; dealership claimed no work performed but vehicle was in service for 1.5 months
Recalls/TSBs owners mention: Hyundai America contacted; no documented assistance or investigation result
No reverse gear after engine replacement
Vehicle has no reverse gear after engine replacement. Scope inspection confirms reverse gear mechanism is missing or failed. Owner has driven 4 years without reverse.
When: Couple months after engine replacement (March 2017)
Symptoms owners cite: No reverse gear engagement; Vehicle will not move in reverse
Repairs/costs cited: Scope inspection performed; no reverse mechanism found; repair unknown
Recalls/TSBs owners mention: Dealership stated no recall applies to this vehicle for reverse gear issue
Electrical module failures and wiring harness short circuits
Engine control module (ECM) fails or becomes 'fried.' Wiring harness develops short circuits. Multiple electrical issues cascade after repairs, with dashboard lights malfunctioning and sensors reporting false codes.
When: Various; one incident after mechanic test-drive attempted (500 miles)
Symptoms owners cite: ECM failure; Wiring harness short circuit; Check engine light on; ABS warning light on; Hard to start; Abnormal electrical burning smell; Brake pedal freezes preventing start
Codes mentioned: Check engine light, ABS warning light
Repairs/costs cited: ECM replaced; wiring harness replaced; issues persisted; no lasting solution documented
Recalls/TSBs owners mention: Manufacturer contacted but no assistance offered
Transmission slipping immediately after replacement
Transmission is replaced but immediately begins slipping on the drive home or shortly after pickup from dealership. Remanufactured units reported to fail quickly.
When: Same day as replacement pickup; within days of installation
Symptoms owners cite: Transmission slips; Loss of power; Vehicle jerks and loses speed while moving
Repairs/costs cited: Remanufactured transmission installed but began slipping same day; repair history includes prior engine failure and alternator replacements
Recalls/TSBs owners mention: Not documented
Alternator failure (primary and secondary)
Alternator fails while driving in traffic. Replacement alternator fails again shortly after installation. Multiple electrical failures compound the issue.
When: Various timing; failures occur in close sequence
Symptoms owners cite: Loss of electrical power while driving; Vehicle stalls in traffic
Repairs/costs cited: Alternator replaced twice in short succession; issue persists with transmission and electrical concerns
Recalls/TSBs owners mention: Not documented
Fuel system pressure and delivery issues post-engine replacement
After engine replacement, vehicle exhibits fuel delivery problems, lurching at random, and fuel efficiency degradation. Cruise control shuts off due to lurching. Check engine light comes on repeatedly; dealership unable to diagnose after multiple visits.
When: Immediately after short block replacement (Oct 2019); ongoing through 2020
Symptoms owners cite: Car lurches at random times; Not getting consistent fuel; Cruise control disengages; Check engine light comes on; No warning before stall event
Codes mentioned: Check engine light
Repairs/costs cited: Short block replaced; HSG belt replaced (did not fix); software updates applied; codes cleared without fixing root cause; six-week shop visit with no resolution; 337 miles added by dealership during repair attempts
Recalls/TSBs owners mention: Software updates; code resets; admitted inability to duplicate or find issue
Synthesized from 93 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Had powertrain trouble with your 2012 Hyundai Sonata?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the powertrain problem on the 2012 Hyundai Sonata?
It's a meaningful issue. 93 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $2,500.
At what mileage does the powertrain typically fail?
Across the 64 complaints that reported odometer mileage, most powertrain failures cluster between 49,000 and 120,000 miles, with the median around 88,000. A quarter of owners report trouble before 49,000; a quarter make it past 120,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $2,500 for powertrain repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to powertrain?
No active recalls currently cover powertrain issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2012/Hyundai/Sonata.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.