Faulty ignition coil B (primary or secondary winding failure); Damaged or corroded wiring or connector at the coil B harness; Open or short circuit in the primary circuit between the PCM and coil B; Failed spark plug or excessive spark plug gap causing the coil to overheat and fail; PCM driver circuit failure for coil B (less common); Moisture or oil intrusion into the coil or connector causing intermittent faults

DTC codes / P03xx · Ignition system and misfire / P0352

P0352Ignition Coil B Primary/Secondary Circuit Malfunction

Q: What does code P0352 mean?

Ignition Coil B Primary/Secondary Circuit Malfunction. P0352 indicates that the powertrain control module (PCM) has detected an abnormal condition in the primary or secondary circuit of ignition coil B, which is typically the coil for cylinder number two in the engine's firing order. The PCM monitors the coil's electrical circuit and sets this code when the current or voltage falls outside the expected range during operation, pointing to a fault in the coil itself, its wiring, or the control signal from the PCM.

P0352 indicates that the powertrain control module (PCM) has detected an abnormal condition in the primary or secondary circuit of ignition coil B, which is typically the coil for cylinder number two in the engine's firing order. The PCM monitors the coil's electrical circuit and sets this code when the current or voltage falls outside the expected range during operation, pointing to a fault in the coil itself, its wiring, or the control signal from the PCM.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms
Engine misfire that may be felt as a rough idle, hesitation, or stumbling during acceleration
Reduced engine power and poor fuel economy due to incomplete combustion in one cylinder
Shaking or vibration that worsens under load, such as when climbing a hill or towing
In some cases, a flashing check engine light if the misfire is severe enough to damage the catalytic converter

Common causes, most likely first

Faulty ignition coil B (primary or secondary winding failure)
Damaged or corroded wiring or connector at the coil B harness
Open or short circuit in the primary circuit between the PCM and coil B
Failed spark plug or excessive spark plug gap causing the coil to overheat and fail
PCM driver circuit failure for coil B (less common)
Moisture or oil intrusion into the coil or connector causing intermittent faults

How to diagnose and fix it

Perform a visual inspection of coil B, its connector, and wiring for damage, corrosion, or oil contamination
Swap coil B with a known-good coil from another cylinder (if accessible) to see if the misfire moves with the coil
Use a digital multimeter to check the primary and secondary resistance of coil B against the manufacturer's specifications
Check for battery voltage and ground at the coil B connector with the key on, engine off
Inspect the spark plug for wear, gap, or fouling and replace if necessary
Test the control signal from the PCM to coil B using an oscilloscope or a noid light designed for ignition coils
If all electrical checks pass, diagnose the PCM driver circuit or replace the PCM as a last resort

Common Misdiagnosis Traps for P0352

A misfire code for coil B does not automatically mean the coil is defective; a worn spark plug or a faulty injector can cause similar symptoms and set related codes.
Intermittent wiring faults often occur where the harness flexes near the coil or where it rubs against engine components, so wiggle-testing the harness while the engine runs can reveal the problem.
On some engines, coil B is not necessarily the second cylinder in the firing order; always consult the service manual for the correct cylinder identification to avoid replacing the wrong coil.
Oil leaking from a failed valve cover gasket can soak the coil boot and cause a short, leading to P0352 without any visible damage to the coil windings.
A weak battery or charging system issue can cause low voltage to the coils, triggering P0352 and other coil codes simultaneously, so check the charging system before condemning parts.

Can I keep driving with P0352?

It is generally safe to drive with P0352 if the engine is running smoothly and the check engine light is steady, but avoid heavy acceleration or towing until the fault is repaired. If the check engine light is flashing or the engine is misfiring severely, stop driving to prevent catalytic converter damage.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.