This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
Definition
Ignition Coil C Primary/Secondary Circuit Malfunction
Meaning
The ignition system in your vehicle uses electricity from the battery and alternator to ignite the fuel in engine valves via spark plugs and coils. Once ignited by the coils, the fuel combusts and moves moving the pistons to turn the crankshaft and transfer energy to the main drive shaft via the transmission.
In other words, your ignition system makes sure that your internal combustion engine combusts efficiently and creates the rotary cycles that power your car.
Sometimes, due to wear and tear or lack of maintenance, the ignition system on a vehicle malfunctions or fails to combust fuel in all chambers efficiently. When that happens, your car’s onboard diagnostic system saves a trouble code in the system and illuminates the check engine light.
If you plug in an OBDII scanner and see a P0353 code, that means you have a problem with your powertrain related to the ignition system/engine misfire. P0353 refers specifically to a malfunctioning ignition coil C (or number 3) in the primary or secondary circuit.
Causes
If you’ve got a failing/malfunctioning ignition coil, there are a few different root causes to check first:
- Defective/damaged ignition coil (they wear out over time)
- Corroded/defective/damaged ignition coil connector (happens over time with exposure to the air and adverse weather conditions)
- Shorted, corroded, damaged or defective ignition coil driver circuit wiring (also caused by time and exposure to the elements)
- Loose connection at coil (normal engine vibration can cause this to occur over a long enough time period)
- Broken connector locks (they degrade over time and break when they have hit the point of no return)
- Damaged or defective ECM (extremely rare scenario, but still worth mentioning)
Symptoms
Here’s what you can expect from a vehicle that has coded P0353:
- Check engine soon/Warning light illuminated on the dashboard
- Rough idle when standing/not in motion
- Engine misfire when idling
- Decreased vehicle performance due to ignition timing issues (thus the saying “not firing on all cylinders” meaning you aren’t at your best)
Diagnosis
There’s a specific process to follow when you are determining the root cause of this trouble code. Here’s a quick rundown of the steps you need to take in the correct order:
1. Connect an OBD-II scanner to check for a stored P0353 trouble code. Here's a great one we use daily.
2. Perform a visual check of all wiring and connectors to see if there is any damage, wear or corrosion
3. Listen to engine run to determine if the engine misfires are happening regularly or intermittently
4. Check Ignition coil C for loose or corroded prongs.
5. Inspect ignition coil C for damaged or shorted wires/connectors
6. Check the Hertz signal to ignition coil C with a multimeter. If the meter reads 5 and 20 Hertz, the coil is damaged
7. Use a multimeter to test the voltage of the coil driver circuit
8. Check resistance and continuity between ground and coil driver circuit with a multimeter.
9. Inspect camshaft sensors for damaged for any damaged or defective modules.
Common mistakes
While it is rare for an ECM to malfunction or require replacement, a P0353 code can be stored by the system if the ECM is faulty. Be sure to completely diagnose any possible wiring faults or connector issues before diagnosing the ECM as the cause.
Replacing an ECM is a costly and labor intensive process, and you should always do everything you can to make sure there are no other possible causes before making a determination about diagnosis.
How serious
Even with an ignition coil trouble code, you vehicle should still be perfectly safe to drive. A P0353 is unlikely to cause any safety hazards, and the worst you will probably experience is a rough idle with some potential for stalling.
However, if you do see P0353, your vehicle needs to be checked out ASAP by a qualified mechanic.
Diagnostics and repairs can get expensive quickly if you leave you don’t get your vehicle serviced right away and your ignition system is malfunctioning.
What Repairs Can Fix This Code?
The following will generally resolve most P0353 codes:
- Repair or replace any damaged or corroded ignition coils
- Replace damaged or faulty ignition coil wires and connectors
- Replace shorted or damaged wire to coil drive circuit
- Repair or replace damaged ECM (rare)
- Clear all codes, test-drive the vehicle, and scan again to see if any codes reappear
Related Codes
- P0351: Ignition Coil Primary/Secondary Circuit
- P0351: Ignition Coil "A" Primary/Secondary Circuit
- P0352: Ignition Coil "B" Primary/Secondary Circuit
- P0354: Ignition Coil "D" Primary/Secondary Circuit
- P0355: Ignition Coil "E" Primary/Secondary Circuit
- P0356: Ignition Coil "F" Primary/Secondary Circuit
- P0357: Ignition Coil "G" Primary/Secondary Circuit
- P0358: Ignition Coil "H" Primary/Secondary Circuit
- P0359: Ignition Coil "I" Primary/Secondary Circuit
- P0360: Ignition Coil "J" Primary/Secondary Circuit
- P0361: Ignition Coil "K" Primary/Secondary Circuit
- P0362: Ignition Coil "L" Primary/Secondary Circuit
Is it OK to drive with a bad ignition coil?
Despite the fact that Coil On Plugs (COPs) can be defective, you can still drive, but it is not recommended. A defective spark ignition system will prevent you from driving. It is possible to damage other engine components by driving with a faulty coil pack.
Conclusion
Fixing a P0353 error code is generally just a matter of checking all your wiring connections and ensuring that your plugs, wires and other ignition components are in good shape.
While it’s not a crisis auto repair, you should still get all ignition system issues repaired ASAP to forestall more expensive repairs later.
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