P3403
System
Powertrain (Engine)
Benötigter Scanner
Full-system scanner (engine, ABS, SRS, transmission, service resets)

Cylinder 3 Deactivation System Performance

Understand P3403, common causes, and the right FOXWELL scanner to diagnose it.

Active Fuel Management (AFM/DOD) system cannot deactivate or reactivate cylinder 3 as commanded — common on GM V6/V8 with cylinder deactivation.

Häufige Symptome

  • Ticking or misfire on affected cylinder
  • P0303 may accompany
  • Rough idle
  • Check engine light
  • Reduced fuel economy benefit lost

Typische Ursachen

  • Failed AFM lifter on cylinder 3
  • Low oil pressure to AFM solenoids
  • Wrong oil viscosity or low oil level
  • AFM solenoid oil passage blockage
  • Collapsed AFM lifter on cylinder 3

Welchen Scanner brauchen Sie?

Full-system scanner (engine, ABS, SRS, transmission, service resets)

Nutzen Sie Live-Daten und Freeze Frame, bevor Sie Teile tauschen. ABS-, SRS- und U-Codes erfordern meist einen Vollsystem-Scanner.

Diagnose-Tipps

  • Freeze Frame erfassen, wenn der Code erstmals gesetzt wird
  • Code erst nach Behebung der Ursache löschen
  • Auf verwandte pending codes prüfen
  • Batteriespannung über 12,4 V prüfen, bevor Sie Sensoren verdächtigen

Empfohlene FOXWELL Scanner

Häufig gestellte Fragen

Can I diagnose P3403 with a basic code reader?
P3403 may set in the engine module, but related diagnostics often benefit from an enhanced or full-system scanner with live data and freeze frame.
Is it safe to drive with P3403?
It depends on the code and symptoms. Flashing check engine lights and misfire codes should be addressed immediately. Consult a professional if unsure.