A P0277 code on your 2021 Honda Odyssey indicates a high voltage condition in the cylinder 6 fuel injector circuit. The Odyssey's V6 relies on all cylinders for the smooth, quiet operation families expect.
Odyssey Engine Details
The 2021 Honda Odyssey is powered by the 3.5L J35 V6 producing 280 horsepower. This proven engine uses port fuel injection on all six cylinders. Cylinder 6 is located on the rear bank, closest to the firewall and transmission.
High Circuit Analysis
High voltage indicates an open circuit—no current is flowing through the injector. The ECM commands injector operation but sees no current draw, leaving the voltage at the reference level. Causes include disconnected connectors, broken wires, or injector coils that have failed open internally.
Diagnostic Process
Access the cylinder 6 injector on the rear bank—this requires working near the firewall in the cramped minivan engine bay. Verify connector is fully seated. Measure injector resistance; infinite ohms indicates an open coil. Test wiring continuity from the connector back to the ECM. Check for any recent service that might have disturbed connections.
Repair Requirements
An open injector requires replacement. Honda J-series injectors are readily available. Access to rear-bank cylinders requires patience but is achievable. If wiring is damaged, locate and repair the open section. After repair, clear codes and verify through multiple drive cycles that the family minivan runs smoothly again.