P3400: owner reports and bulletins

Powertrain (generic, all makes). We haven't written the explanation for this code yet. Below is what owners and manufacturers have filed with NHTSA.

Got P3400 on your scanner? Tell the mechanic your year, make, model and any symptoms and you'll get the likely cause and what to check first. Ask about this code.

What owners report to NHTSA

25 complaints filed with NHTSA mention P3400, 23 of them since 2015, across 7 different models. The component owners most often filed it under: engine.

Most-reported models

VehicleComplaintsModel years reported
HONDA ODYSSEY112008, 2009, 2010, 2012, 2016
HONDA ACCORD CROSSTOUR42010
HONDA ACCORD42008, 2010, 2011, 2012
HONDA PILOT32010, 2011, 2013

Manufacturer service bulletins that name P3400

20 technical service bulletins and manufacturer communications filed with NHTSA mention P3400, from 4 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:

  • MAZDA CX-3 (2016, 2017, 2018, 2019), bulletin 10201861: If you receive a customer concern about the CHECK ENGINE light coming on and DTC P3400 (cylinder deactivation system malfunction) stored, the cylinder deactivation oil control valve may be plugged with plastic debris fro…
  • MAZDA MAZDA6 (2018, 2019, 2020), bulletin 10180714: If you receive a customer concern about the CHECK IN light coming on and DTC P3400 (cylinder deactivation system malfunction) stored, the cylinder deactivation oil control valve may be plugged with plastic debris from th…
  • HONDA RIDGELINE (2017), bulletin 10202599: Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2017 Odysseys, Pilots & Ridgelines with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P2652 (Rocker Arm Oil P…
  • ACURA RDX (2017), bulletin 10202603: Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for 2017 MDXs, RDXs, RLXs & TLXs with a client complaint of the Malfunction Indicator Light (MIL) on with the DTC P2652 (Rocker Arm Oil Pressure Switch B…
  • HONDA ODYSSEY (2017), bulletin 10206442: Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2017 Odysseys, Pilots & Ridgelines with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P2652 (Rocker Arm Oil P…
  • HONDA PILOT (2017), bulletin 10206785: Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2017 Odysseys, Pilots & Ridgelines with a customer complaint of the Malfunction Indicator Light (MIL) on with the DTC P2652 (Rocker Arm Oil P…

Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.