Faulty ignition coil C (secondary winding failure or internal short); Worn or fouled spark plug on the affected cylinder; Damaged or corroded wiring or connector at coil C; Open or shorted secondary circuit in the harness; PCM internal fault affecting coil control (rare); Ignition coil boot or spring corrosion causing poor contact

DTC codes / Mazda codes / P1362

P1362 · MazdaIgnition Coil C Secondary Circuit

Q: What does code P1362 mean?

Ignition Coil C Secondary Circuit. P1362 on Mazda vehicles means the powertrain control module (PCM) has detected a problem with the secondary circuit of ignition coil C, which is the high-voltage side that fires the spark plug. The PCM monitors the coil's feedback signal and sets this code when the circuit behaves outside the expected range, often due to a failing coil, a bad plug, or damaged wiring.

P1362 on Mazda vehicles means the powertrain control module (PCM) has detected a problem with the secondary circuit of ignition coil C, which is the high-voltage side that fires the spark plug. The PCM monitors the coil's feedback signal and sets this code when the circuit behaves outside the expected range, often due to a failing coil, a bad plug, or damaged wiring.

SystemPowertrain

Code typeMazda specific

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Symptoms you may notice

Check engine light illuminated, often with no other noticeable symptoms
Engine misfire or rough running, especially under acceleration or load
Reduced engine power or a limp-home mode in some Mazda models
Poor fuel economy or increased emissions
Occasional engine stumble or hesitation at idle
In severe cases, a flashing check engine light indicating a misfire that can damage the catalytic converter

Common causes, most likely first

Faulty ignition coil C (secondary winding failure or internal short)
Worn or fouled spark plug on the affected cylinder
Damaged or corroded wiring or connector at coil C
Open or shorted secondary circuit in the harness
PCM internal fault affecting coil control (rare)
Ignition coil boot or spring corrosion causing poor contact

How to diagnose and fix it

Scan all modules and record freeze-frame data to confirm the fault conditions
Inspect the coil C connector and wiring for corrosion, looseness, or damage
Swap coil C with a known-good coil from another cylinder to see if the misfire moves
Check the spark plug condition and gap on the affected cylinder; replace if worn
Perform a secondary ignition waveform test (if equipped) to compare coil C to others
Measure resistance of the coil primary and secondary windings and compare to specification
Replace the faulty ignition coil and clear the code, then verify the repair with a road test

Don't replace the PCM before checking these

A bad spark plug or a corroded coil boot often sets P1362 without the coil itself being defective, so always inspect the plug and boot first.
Mazda coils can fail intermittently when hot, so a coil that tests good cold may still be the culprit; a heat soak test or swapping coils can reveal the fault.
The secondary circuit includes the coil tower, boot, and spark plug; arcing or carbon tracking on the boot can mimic a failed coil.
P1362 can be set by a poor ground connection at the engine block or coil mounting, which is often overlooked during diagnosis.
After replacing the coil, clear the PCM adaptive memory and perform a misfire monitor relearn procedure if required by the model.

Can I keep driving with P1362?

You can usually drive the car to a repair shop if the check engine light is steady and the engine runs smoothly, but avoid heavy acceleration or towing. If the light flashes or the engine misfires badly, stop driving to prevent catalytic converter damage.

Tools that help

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