The 2022 Volvo XC90 is powered exclusively by turbocharged and supercharged 4-cylinder engines across all variants including B5, B6, and Recharge plug-in hybrid. When a P0305 diagnostic trouble code appears indicating a cylinder 5 misfire, this represents an anomalous diagnostic situation since all XC90 engines have only four cylinders.
Understanding the P0305 Anomaly
The P0305 code translates to "Cylinder 5 Misfire Detected" in standard OBD-II terminology. However, the XC90's 2.0-liter 4-cylinder engine contains only cylinders numbered 1 through 4. The appearance of this code indicates a diagnostic system irregularity.
Volvo's 4-Cylinder Strategy
Volvo standardized on 4-cylinder engines across their lineup, including the flagship XC90. The B5 (mild-hybrid turbo), B6 (mild-hybrid turbo+supercharged), and Recharge (plug-in hybrid) all use the same 2.0L 4-cylinder base engine. No XC90 has a fifth cylinder.
Diagnostic Protocol
When encountering P0305 on your 4-cylinder XC90, a qualified technician should use Volvo VIDA diagnostics to verify actual misfire counter data for cylinders 1-4. Software updates and communication errors should be investigated.
Possible Causes
This anomalous code may result from ECU software requiring updates, control module communication errors, or diagnostic system issues.