P2306
Ignition Coil C Primary Control Circuit Low
Ignition system
Generic OBD-II
Medium
What it means
P2306 means the engine computer detected low voltage in the primary control circuit of ignition coil "C." When this circuit faults, the coil may not fire its cylinder, producing a misfire, rough running, and reduced power. The usual causes are the coil itself or its wiring and connector rather than the engine internals.
Medium
Can I keep driving? Drivable but not ideal — the affected coil may not fire, causing a misfire that can, over time, damage the catalytic converter.
Common symptoms
What you'll notice
- Check-engine light on (may flash during an active misfire)
- Rough idle or a stumble/miss on that cylinder
- Hesitation and reduced power
- Slightly higher fuel consumption
Common causes
Most likely first
- Corroded or loose connector at ignition coil CLikely
- Control wire shorted to ground or an open in the primary circuitCommon
- Failed ignition coil CCommon
- Poor ground or supply to the coilLess often
- Failed PCM/ECM coil driver (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and identify which cylinder coil C serves for your engine.
- Inspect the coil connector and primary wiring for corrosion, shorts to ground, and opens.
- Swap coil C with a known-good coil to see if the fault follows the coil.
- Check the coil's power and ground and the driver circuit back to the PCM.
- Replace the coil if it fails testing, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2306?+
For short distances, yes, but a dead coil causes a misfire that dumps raw fuel into the exhaust and can overheat the catalytic converter. Fix it promptly, especially if the light is flashing.
Can I just clear P2306?+
It returns quickly unless the coil or its control circuit is repaired.
Related codes
Often seen with P2306
Read & clear P2306 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX