P2308 — Ignition Coil "C" Secondary Circuit
powertrain (engine/transmission)
Is it safe to drive?
Drive with caution Drive with caution and avoid load. Ignition faults cause misfires that quickly overheat and destroy the catalytic converter; if the Check Engine Light flashes, stop and fix it first.
How to diagnose with an OBD scanner
- Read the code and freeze frame Connect an OBD2 scanner, confirm P2308 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the ignition system for damage, corrosion, chafing or poor contact.
- Subsystem check Swap the coil to another cylinder and see if the fault code follows it.
- Subsystem check Inspect spark plugs for wear, oil or carbon tracks and check plug gaps.
- Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2308 does not return.
Approximate repair cost
Repair cost depends on which component actually failed. Typical scenarios for P2308 (parts and labor, USD, independent shop rates): Replace an ignition coil: $150–$380; Repair coil wiring or connector: $80–$250; Replace spark plugs: $90–$250. Overall, fixing P2308 usually costs between $80 and $380. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Common questions
How much does it cost to fix P2308?
Replace an ignition coil — $150–$380; Repair coil wiring or connector — $80–$250; Replace spark plugs — $90–$250. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.
Is it safe to drive with P2308?
Drive with caution and avoid load. Ignition faults cause misfires that quickly overheat and destroy the catalytic converter; if the Check Engine Light flashes, stop and fix it first.
What does OBD2 code P2308 mean?
Ignition Coil "C" Secondary Circuit (P2308): a powertrain (engine/transmission) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by worn spark plugs or wrong plug gap, faulty ignition control circuit in the ECM, damaged coil wiring or connector.
What is the most common cause of P2308?
The most common causes are: worn spark plugs or wrong plug gap, faulty ignition control circuit in the ECM, damaged coil wiring or connector.
Will P2308 clear itself?
Sometimes P2308 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.
What does P2308 mean?
Behind P2308 is a specific failure in the ignition system: ignition coil "C" secondary circuit. The onboard computer stores it in the powertrain (engine/transmission) group after verifying the fault over repeated checks.
To set P2308, the control module compares live readings of the ignition system against calibrated limits, usually over several drive cycles. Alongside the code it stores a freeze frame — a snapshot of rpm, load, coolant temperature and vehicle speed at the moment of failure. Reading that snapshot first saves diagnostic time.
What causes P2308?
- damaged coil wiring or connector
- worn spark plugs or wrong plug gap
- faulty ignition control circuit in the ECM
- moisture or oil in the spark plug wells
- failed ignition coil or coil pack
Common symptoms of P2308
- increased fuel consumption
- Check Engine Light on
- loss of power and jerking
- misfires under load or at idle
- hard starting, especially in damp weather
How to diagnose P2308
- Connect an OBD2 scanner, confirm P2308 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
- Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
- Visually inspect the wiring harness and connectors related to the ignition system for damage, corrosion, chafing or poor contact.
- Swap the coil to another cylinder and see if the fault code follows it.
- Inspect spark plugs for wear, oil or carbon tracks and check plug gaps.
- Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P2308 does not return.
How to fix P2308
Start with the cheapest and most common causes before replacing expensive parts:
- Replace an ignition coil — $150–$380
- Repair coil wiring or connector — $80–$250
- Replace spark plugs — $90–$250
How much does it cost to fix P2308?
Repair cost depends on which component actually failed. Typical scenarios for P2308 (parts and labor, USD, independent shop rates):
- Replace an ignition coil: $150–$380
- Repair coil wiring or connector: $80–$250
- Replace spark plugs: $90–$250
Overall, fixing P2308 usually costs between $80 and $380. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.
Can you drive with P2308?
Drive with caution and avoid load. Ignition faults cause misfires that quickly overheat and destroy the catalytic converter; if the Check Engine Light flashes, stop and fix it first.