Ignition coils are responsible for providing the spark plugs with the necessary high voltage to ignite the air-fuel mixture inside the combustion chambers.
If the check engine light switches on and you find the P0352 code logged on your code reader, it means that there is a potential problem with the cylinder #2 ignition coil or its circuit.
What Does Code P0352 Mean?
The engine control module (ECM) alerts DTC P0352 – or “Ignition Coil B Primary/Secondary Circuit Malfunction”- It indicates that there’s a potential problem in either the primary (computer) side or the secondary (spark plug) side of the ignition coil “B” (cylinder #2) circuit.
DTC P0352 indicates a problem in the conversation between the ECM and the ignition coil. Understanding the link between these two elements is essential to determine what components could be at fault. Let’s explore the relationship further before we identify potential causes.
Low-voltage power from the battery travels to the ignition coil, where it is transformed into high-voltage power that’s routed to the spark plug.
Specifically, the battery’s power enters the primary coil and transfers to the secondary coil, where it enters a magnetic field- created by the spinning secondary coil and then fires the spark plug to incite combustion.
The ECM monitors this process to ensure correct cylinder-fire timing and alerts code P0352 when conditions fall outside this routine procedure.
Potential Causes of a P0352 Code
- Short to voltage or ground on COP driver circuit.
- Carbon buildup in the Throttle Body air passages.
- Open on COP driver circuit.
- Damaged/corroded/worn coil wiring.
- Loose connection at coil or broken connector locks.
- Defective Idle Air Control Valve or Electronic Body.
- Bad Coil (COP) Faulty Powertrain Control Module.
P0352 Code Symptoms
- The car engine may idle roughly
- The engine might misfire on acceleration
- The malfunctioning indicator lamp can start appearing
- There can be a lack of power in the engine, especially under a heavy load
- Issue of engine hesitation
- There can be hard-to-start conditions of the engine
- Abnormal vibrations may be felt at idle or while driving
How to Fix P0352
The specific solution required to fix DTC P0352 depends on the diagnosis. In the case of faulty components, replacing the damaged component -such as the ECM, coil pack wiring harness, spark plug wires, coil pack, or spark plug-can solve at least one problem.
Replacing a cracked vacuum line or leaky intake manifold gasket can also potentially fix the issue.
Unfortunately, some P0352 codes may be caused by multiple issues that do not fully reveal themselves at first glance.
Follow the below steps to fix it Malfunction:
- Try wiggle-testing the wiring at the #2 coil and along the wiring harness to the PCM. If manipulating the wiring causes the misfire to surface, repair the wiring problem.
- Check for poor connection at the coil connector. Verify the harness isn’t misrouted or chafing on anything. Repair as necessary If the engine is misfiring presently, stop the engine and disconnect the #2 coil wiring connector.
- Then start the engine and check for a driver signal to the #2 coil. Using a scope will give you a visual pattern to observe, but since most people don’t have access to one there’s an easier way.
- Use a Voltmeter in the AC Hertz scale and see if there’s a Hz reading of between 5 and 20 or so that indicates the driver is working. If there is a Hertz signal, then replace the #2 ignition coil.
- If you don’t detect any frequency signal from the PCM on the ignition coil driver circuit indicating the PCM is grounding/ungrounding the circuit (or there is no visible pattern on the scope if you have one) then leave the coil disconnected and check for DC voltage on the driver circuit at the ignition coil connector.
- If there is any significant voltage on that wire then there is a short voltage somewhere. Find the short and repair it.
- If there is no voltage on the driver circuit, then turn the ignition off. Disconnect the PCM connector and check the continuity of the driver between the PCM and the coil. If there is no continuity repair the open or short to ground in the circuit.
- If continuity is present, then check for resistance between the ground and the ignition coil connector. There should be infinite resistance. If there isn’t, repair the short to ground in the coil driver circuit.
How Much Does It Cost to Fix a P0352 Code?
To fix an OBD-II P0352 code, which indicates a problem with the ignition coil “B” primary circuit, you can expect to pay anywhere between $100 and $300 depending on your vehicle, including the cost of the replacement ignition coil and labor for installation; with the majority of the cost usually attributed to the coil itself.