P0700 on Subaru: How to Diagnose & Fix
Transmission Control System Malfunction
8 Subaru models · 12 documented issues · 8 critical · $200-$9,000 repair
P0700 on Subaru by model: symptoms, diagnosis and fix
The Lineartronic CVT (TR690) in 2014-2021 Foresters can develop shuddering, hesitation, and in severe cases, complete failure. Symptoms typically begin around 60,000-100,000 miles. The CVT chain can stretch, causing slippage and shudder during light acceleration. The torque converter can also develop issues. Subaru extended CVT warranty to 10 years/100,000 miles under Customer Satisfaction Program WTY-72. Multiple software updates have been released to address shifting behavior.
Common Symptoms
- Shuddering during light acceleration at 15-40 mph
- Hesitation or delay when accelerating from a stop
- CVT whining or droning noise
- Rough engagement into Drive or Reverse
- Transmission warning light on dashboard
How to Fix
Have the dealer check for and apply the latest CVT software updates (TSB 16-103-17R). Perform CVT fluid change with Subaru CVT Fluid Lineartronic II (SOA427V1700). If shuddering persists, torque converter replacement or complete CVT replacement may be needed. Verify coverage under Subaru's 10-year/100,000-mile CVT warranty extension.
The Lineartronic CVT can develop shudder, hesitation, or jerky operation, especially during light acceleration at low speeds. Subaru has updated CVT software multiple times to address these concerns.
Common Symptoms
- Shudder during light acceleration
- Hesitation from stop
- Jerky operation at low speeds
- CVT whine or noise
- Delayed engagement
How to Fix
Have dealer update CVT software to latest version. CVT fluid change may help. In severe cases, valve body or CVT replacement may be needed. Subaru extended CVT warranty on some vehicles.
Owner tips & cautions
- TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
- TipSearch Subaru Outback forums and owner groups for real-world experiences and DIY guides
- TipGet multiple quotes from independent mechanics - dealer prices can be 2-3x higher for the same repair
Early Lineartronic CVT Outbacks (2010-2015) have documented internal CVT failures — most commonly valve-body faults, but also chain/pulley and pressure-control problems — that can cause harsh or delayed engagement, RPM flare, jerking, limp mode, or complete loss of drive. Subaru acknowledged the problem with a CVT Warranty Extension to 10 years / 100,000 miles covering the CVT and everything associated with it (valve bodies, internal parts, harnesses, and leaks) on 2010-2015 Legacy/Outback (and related models). A revised/upgraded valve body is installed at repair. This is separate from the low-speed torque-converter shudder complaint; here the transmission can set fault codes and go into failsafe. Out of warranty, a full CVT replacement is a multi-thousand-dollar repair.
Common Symptoms
- Harsh or delayed engagement into gear
- RPM flare / slipping under acceleration
- Jerking or shuddering
- Transmission warning light / limp mode
- Whining or loss of drive
How to Fix
If you experience harsh/delayed engagement, flaring, jerking, or a transmission warning, scan for CVT codes and get it evaluated quickly. First verify the vehicle is within (or was serviced under) the 10-year/100,000-mile CVT Warranty Extension — if so the valve-body or CVT repair should be free; escalate to Subaru of America if a dealer initially denies coverage, since owners report success on valve-body claims. Keep CVT fluid at the correct level/spec and address any leaks promptly, as low pressure accelerates valve-body wear. Out of warranty, a rebuilt/updated valve body is far cheaper than a complete CVT unit — get a diagnosis of the specific failed component before authorizing a full replacement.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Subaru 31706AA331 CVT Control Valve Body
early CVT valve body only after TCM diagnosis proves the valve-body fault Fitment/availability: 2010-2012 Outback 2.5-liter EJ253 CVT branch; confirm VIN and production date Fitment/availability: ships in 1-2 business days with Add to Ca…
- Genuine Subaru 31825AA055 CVT Control Valve Kit
later 2.5-liter CVT valve body only after TCM diagnosis proves the fault Fitment/availability: 2013-2015 Outback 2.5-liter FB25 CVT branch; current supersession of 31825AA050-054, confirm VIN Fitment/availability: Add to Cart live when r…
- Genuine Subaru 31706AA144 High-Torque CVT Control Valve Body
2015 3.6R high-torque CVT valve body after exact diagnosis and VIN selection Fitment/availability: 2015 Outback 3.6R CVT branch within this card; current supersession of production-specific 31706AA140/141, confirm VIN Fitment/availabilit…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (3)
The Ascent's high-torque Lineartronic CVT (TR730 - the largest CVT Subaru has produced) paired with the 2.4L turbo FA24 engine exhibits hesitation from stops, harsh engagement when shifting from Park to Drive/Reverse, and surging at low speeds. The TR730 CVT must handle significantly more torque than Subaru's other CVTs, leading to durability concerns. Multiple TSBs have addressed calibration issues. Some owners report complete CVT failure under 60,000 miles.
Common Symptoms
- 1-2 second hesitation when accelerating from a stop
- Harsh thunk when shifting from Park to Drive or Reverse
- Surging or bucking at low speeds in parking lots
- Shuddering during light acceleration at 25-40 mph
- Transmission warning light
- Burning smell from transmission area
How to Fix
Have dealer apply latest TCM software calibration (multiple TSBs released). Perform CVT fluid drain and refill with Subaru High Torque CVT Fluid (SOA427V1660) - note this is different from the standard CVT fluid. If hesitation persists after software update, valve body replacement may be needed. For complete failure, Subaru reman CVT is available. All Ascents have 10-year/100,000-mile CVT warranty from factory.
Sources for this issue (1)
The Ascent's TR730 high-torque CVT develops valve body failures that cause erratic shifting, harsh engagement, and transmission warning lights. The valve body controls hydraulic pressure to the CVT pulleys and chain, and when solenoids or passages within it fail, the transmission cannot maintain proper ratio control. This issue is distinct from the CVT hesitation TSB and represents a hardware failure rather than a calibration issue.
Common Symptoms
- Transmission warning light illuminated
- Harsh thud when shifting from Park to Drive
- CVT slipping or flaring RPMs under load
- Shuddering at highway speeds
- Vehicle going into limp mode (limited to low speeds)
- Burning fluid smell
How to Fix
Diagnose with dealer scan tool to confirm valve body solenoid fault codes. Valve body replacement resolves the issue in most cases — this is a less expensive repair than full CVT replacement. If the CVT has been operated with a failed valve body for an extended period, internal damage may necessitate full CVT replacement. Covered under Subaru's 10-year/100,000-mile CVT warranty.
Sources for this issue (4)
A TCU programming error allows the Lineartronic CVT to engage before the drive chain is fully secured, causing chain slippage that fragments the chain guide. Owners report shudder, hesitation, irregular noises and MIL illumination; in worst cases chain breakage causes loss of motive power. This superseded the earlier WUV-07 recall and is the basis for the April 2024 class-action settlement covering 2019-2020 Ascents.
Common Symptoms
- shudder on acceleration
- hesitation
- whining or rattling from CVT
- CEL/MIL illuminated
- loss of forward propulsion
- P0700 / P2820-type codes
How to Fix
Verify recall WRK-21 / 21V-955 is completed at a Subaru dealer (free TCU reprogram, chain-slip data inspection, replacement of CVT if slippage is found, plus oil cooler add). Class-action settlement (final approval April 18, 2024) extends powertrain warranty to 8yr/100k for affected VINs and provides reimbursement vouchers ($400-$750) for prior repair attempts.
Sources for this issue (3)
P0700 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0700 mean on a Subaru?
P0700 stands for "Transmission Control System Malfunction." P0700 is a general code indicating the transmission control module (TCM) has detected a fault somewhere in the transmission control system and has requested the check engine light be turned on. By itself it doesn't pinpoint the problem — it's an 'umbrella' code that tells you to look for additional, more specific transmission codes stored alongside it. The actual fault could be electrical, a sensor, a solenoid, or an internal transmission issue. You may notice harsh or delayed shifts, slipping, or the transmission going into a protective 'limp' mode. On Subaru it is documented across 8 models: Forester, Outback, Ascent, Crosstrek, Legacy, WRX, BRZ, Impreza.
What are the most common causes of P0700?
The most common causes of P0700 are: Stored companion transmission codes pointing to the real fault, Faulty shift solenoid or pressure control solenoid, Low, dirty, or degraded transmission fluid, Faulty transmission speed or input/output sensor, Wiring, connector, or ground problems at the transmission, Failing transmission control module (TCM), Internal transmission mechanical wear or clutch problems, Valve body fault or sticking valves. The specific cause varies by vehicle.
How much does it cost to fix P0700 on a Subaru?
Published repair estimates on Subaru range from $200 to $9,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0700 on a different make?
View P0700 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.