P0354 — Ignition Coil "D" Primary/Secondary Circuit Malfunction (Cylinder 4)
An electrical fault has been detected in the ignition coil circuit for cylinder 4 — open primary winding, short to ground, or short to supply. The ECU disables the coil to protect its driver and the cylinder misfires.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Ignition coil
- Ignition coil wiring
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Coil primary winding open or shorted
- Wiring or connector fault
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.