Volkswagen service campaign Circular 24TT_20260421
Volkswagen filed this with NHTSA as a service campaign dated Apr 21, 2026, received May 5, 2026, about the engine. It names 1 model year (2026). A service campaign is not a safety recall — there is no NHTSA campaign number and no federal requirement — but it is usually work the manufacturer pays for on the vehicles it names; the dealer checks the VIN against the manufacturer’s list.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationUnder this service action, updated engine control module (ECM) software will be installed to provide robustness improvements to the ECM calibration for the turbocharger variable turbine geometry (VTG) actuator endpoints. This has no impact on vehicle emissions. Updated affected vehicles chart. Added note to the work instructions regarding fault code P160900.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| Circular 24TT_20260421 | Service campaign | Apr 21, 2026 | 11032212 | not yet checked |
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themA vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
Common questions
Source: NHTSA, 49 CFR 579.5Is Volkswagen Circular 24TT_20260421 a recall?
No. A service campaign is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the Circular 24TT_20260421 repair free?
A service campaign is usually paid by the manufacturer on the vehicles it names, within the terms and time limit the document sets; the dealer checks the VIN against the manufacturer’s list.
Which vehicles does Circular 24TT_20260421 cover?
The manufacturer filed it against 1 model year: 2026 Volkswagen Tiguan. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.