Failed ignition coil B (open or shorted secondary winding); Worn or fouled spark plug on the affected cylinder increasing coil stress; Damaged or corroded coil connector or harness wiring; Faulty ignition coil capacitor or noise suppressor shared with the coil circuit; PCM driver circuit fault or poor ground at the coil mounting point; Moisture intrusion into the coil boot or connector causing secondary voltage leakage

DTC codes / Mazda codes / P1361

P1361 · MazdaIgnition Coil B Secondary Circuit

Q: What does code P1361 mean?

Ignition Coil B Secondary Circuit. P1361 on a Mazda means the powertrain control module (PCM) has detected an abnormal condition in the secondary circuit of ignition coil B, which is the high-voltage side that fires the spark plug. The PCM monitors the coil's feedback signal and flags the code when the expected voltage pattern is missing or out of range, indicating a misfire risk on the affected cylinder.

P1361 on a Mazda means the powertrain control module (PCM) has detected an abnormal condition in the secondary circuit of ignition coil B, which is the high-voltage side that fires the spark plug. The PCM monitors the coil's feedback signal and flags the code when the expected voltage pattern is missing or out of range, indicating a misfire risk on the affected cylinder.

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 at first
Rough idle or engine shaking, especially when cold or under light load
Noticeable misfire or hesitation during acceleration
Reduced fuel economy and a slight loss of power
Flashing check engine light under hard acceleration in severe cases
A faint burnt smell or visible arcing near the coil pack in rare instances

Common causes, most likely first

Failed ignition coil B (open or shorted secondary winding)
Worn or fouled spark plug on the affected cylinder increasing coil stress
Damaged or corroded coil connector or harness wiring
Faulty ignition coil capacitor or noise suppressor shared with the coil circuit
PCM driver circuit fault or poor ground at the coil mounting point
Moisture intrusion into the coil boot or connector causing secondary voltage leakage

How to diagnose and fix it

Scan all modules and record freeze-frame data to confirm P1361 is active and not a ghost code
Inspect coil B connector, boot, and spark plug well for corrosion, oil, or moisture
Swap coil B with a known-good coil from another cylinder and see if the misfire follows the coil
Measure secondary resistance of coil B and compare to the manufacturer's specification
Check spark plug condition and gap on the affected cylinder, replacing if worn or fouled
Perform a wiggle test on the coil harness while watching live misfire counters
If the coil and wiring test good, scope the PCM driver signal or substitute a known-good PCM to rule out internal driver failure

What Mazda coil B codes often hide

A bad spark plug or excessive plug gap is a common root cause that gets missed when technicians replace the coil without checking the plug first.
Oil leaking into the spark plug well from a failed valve cover gasket can short the coil boot and set P1361 even when the coil itself tests fine.
On some Mazda engines, a failing ignition coil capacitor shared across the coil circuit can mimic a coil B failure and will set the code again after replacement.
P1361 can be stored intermittently by a loose coil connector that only loses contact during engine vibration, so a static resistance test may pass.
Do not assume the PCM is faulty until coil, plug, and harness are ruled out, because PCM driver failures are rare compared to coil and plug wear.

Can I keep driving with P1361?

You can usually drive short distances to a repair shop, but avoid hard acceleration and sustained high-speed driving because a persistent misfire can overheat the catalytic converter. If the check engine light is flashing, stop driving and have the vehicle towed.

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.