P173A: How to Diagnose & Fix — Gear Selector Position Sensor 1 Signal Implausible (DSG Mechatronic)
2 vehicles · 1 makes · $900-$5,500 repair
How to diagnose and fix P173A: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Volkswagen Eos · 2007–2016
Eos models equipped with the wet-clutch 6-speed DSG (DQ250) and the later 7-speed dry-clutch DSG (DQ200) commonly develop dual-clutch transmission faults, especially after ~100,000 km. The mechatronic control unit (valve body + solenoids) and internal rubber seals fail, and the clutch packs wear prematurely. Owners report jerky/harsh shifting (notably 2nd-to-1st downshifts and in 'S' mode), a distinct double-thud when coming to a stop, delayed or missing gear engagement, hesitation pulling away, and intermittent limp-mode where the box drops to neutral. There is also a related NHTSA recall (09V333000) for 2009-2010 cars where an insufficiently crimped DSG temperature-sensor wire could trigger an abrupt shift to neutral. Lack of the required ~60k km DSG fluid/filter service accelerates failure.
Common Symptoms
- Harsh or jerky shifting
- Double thud when stopping
- Delayed gear engagement
- Hesitation pulling away
- Transmission drops to neutral / limp mode
- Shudder on takeoff
How to Fix
Diagnose with VCDS to read mechatronic/solenoid fault codes before parting. Many cases are resolved by replacing the mechatronic unit, but worn clutch packs may require a clutch pack change or a full gearbox replacement. Perform DSG fluid and filter service every ~60,000 km (40,000 mi) to prevent premature failure. Ensure the 09V333000 temperature-sensor recall was completed on 2009-2010 cars.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Blau F2A1036-ERL-F Eos DQ250 fluid-and-filter service kit
perform the scheduled DQ250 filter and G 052 182 A2-compatible fluid service using the temperature-controlled level procedure Fitment/availability: 2007-2016 Volkswagen Eos with the 6-speed wet-clutch 02E/DQ250 DSG; not DQ200, manual or …
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)
Volkswagen Touran · 2008–2020
Tourans fitted with the 7-speed DSG use the DQ200 dry dual-clutch transmission (codes 0AM/0CW). Two recurring failure modes affect it: the dry clutch packs wear out prematurely (often by 40,000-60,000 miles in stop-start urban use), and the mechatronic control unit suffers electrical/hydraulic faults. The 0AM mechatronic valve-body has a thin-walled accumulator canister that can split and lose high pressure, plus a synthetic-oil issue where the gearbox oil could become conductive and short the control electronics. Symptoms range from jerky shifts to complete sudden loss of drive. VW issued a global recall for the loss-of-drive/oil issue.
Common Symptoms
- Jerky, harsh, or hesitant gear changes
- Hesitation when pulling away from junctions
- Failure to select reverse or 6th/7th gear
- Warning lights / gearbox fault message on dash
- Sudden complete loss of drive
- Transmission going into limp mode
How to Fix
Replace or rebuild the mechatronic unit (or repair the valve body) and/or fit a new clutch pack. For the recall-covered fault, the dealer fix was a software update and switching the gearbox oil to the corrected specification. Regular DSG service (oil and filter, roughly every 40k miles) reduces clutch and mechatronic failures.
Sources for this issue (3)
Find P173A by make
Browse every documented model and issue for your make.
P173A 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 P173A mean?
P173A stands for "Gear Selector Position Sensor 1 Signal Implausible (DSG Mechatronic)." P173A is a VAG (VW/Audi/Skoda/Seat) manufacturer-specific transmission fault code, set by the DSG/dual-clutch automatic transmission control module (mechatronic unit). It means the control unit received an implausible or out-of-range signal from gear selector/gear position sensor 1, so it can no longer reliably confirm which gear is engaged. It is part of the related P173A-P173D family of internal mechatronic position-sensor faults and commonly accompanies erratic shifting, a transmission warning light, or limp mode.
What are the most common causes of P173A?
The most common causes of P173A are: Failed or degraded gear position (magnetic) sensor inside the mechatronic unit, Faulty mechatronic unit / transmission control module circuit board (thermal damage), Contaminated or worn transmission fluid carrying metal particles past the sensor, Damaged wiring, corroded connectors, or poor grounds to the transmission, Broken or worn internal shift fork/selector magnets, Manufacturing defects in early DSG (e.g. 0AM/DQ200) mechatronic units. The specific cause varies by vehicle.
How much does it cost to fix P173A?
Repair costs for P173A range from $900 to $5,500, depending on the vehicle and root cause.
Which vehicles are affected by P173A?
Au7o has documented P173A across 2 vehicle models from 1 manufacturers: Volkswagen.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.