Faulty ignition coil with an open or shorted primary winding; Damaged or chafed wiring in the spark output circuit between the PCM and coil; Corroded or loose electrical connector at the ignition coil or PCM; Failed ignition coil driver inside the PCM (less common but possible); Spark plug with excessive gap or fouling that overloads the coil circuit; Aftermarket or incorrect ignition coil with wrong resistance; Moisture intrusion into the coil connector or wiring harness

DTC codes / Ford codes / P1359

P1359 · FordSpark Output Circuit Fault

Q: What does code P1359 mean?

Spark Output Circuit Fault. P1359 on Ford vehicles means the powertrain control module (PCM) has detected an unexpected condition on the spark output circuit, typically an open, short, or coil driver fault that prevents the PCM from properly triggering one or more ignition coils. The PCM monitors the ignition coil control circuit and sets this code when the commanded spark event does not match the expected electrical feedback.

P1359 on Ford vehicles means the powertrain control module (PCM) has detected an unexpected condition on the spark output circuit, typically an open, short, or coil driver fault that prevents the PCM from properly triggering one or more ignition coils. The PCM monitors the ignition coil control circuit and sets this code when the commanded spark event does not match the expected electrical feedback.

SystemPowertrain

Code typeFord specific

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Symptoms you may notice

Check engine light or service engine soon light illuminated, often with no other noticeable symptoms
Engine misfire, rough idle, or hesitation under acceleration
Reduced engine power or limp mode in some Ford models
Hard starting or no-start condition if the fault affects multiple coils
Poor fuel economy or increased emissions
Flashing check engine light if the misfire is severe enough to damage the catalytic converter

Common causes, most likely first

Faulty ignition coil with an open or shorted primary winding
Damaged or chafed wiring in the spark output circuit between the PCM and coil
Corroded or loose electrical connector at the ignition coil or PCM
Failed ignition coil driver inside the PCM (less common but possible)
Spark plug with excessive gap or fouling that overloads the coil circuit
Aftermarket or incorrect ignition coil with wrong resistance
Moisture intrusion into the coil connector or wiring harness

How to diagnose and fix it

Inspect the ignition coil connectors and wiring for corrosion, chafing, or loose pins, and repair as needed
Swap the ignition coil from the affected cylinder with a known-good coil to see if the misfire moves
Measure the primary and secondary resistance of the suspect ignition coil and compare to Ford specifications
Check for spark at the affected cylinder using a spark tester while cranking the engine
Perform a wiggle test on the spark output circuit wiring while monitoring misfire counters or coil feedback with a scan tool
Check the PCM connector for corrosion or pushed pins, and verify continuity from the PCM to the coil on the control circuit
If all external circuits and coils test good, diagnose the PCM driver circuit or replace the PCM as a last resort

What Ford technicians check before replacing coils

A P1359 is often set by a single failing coil on Ford engines with coil-on-plug ignition, but the code can also appear when the coil driver inside the PCM fails, so always verify the control circuit before condemning the PCM.
On many Ford models, a misfire from a bad spark plug or a coil boot with carbon tracking can trigger P1359 even though the coil itself still tests good on a bench, so inspect the boot and plug well for arcing marks.
Wiring harness chafing near the valve cover or intake manifold is a common hidden cause on older Ford vehicles, and a visual inspection alone may miss internal wire breaks that only show up during engine vibration.
This code does not always mean the coil is dead; a poor ground at the engine block or a weak battery can cause the PCM to see an unexpected spark output signal and set P1359.
After replacing a coil or repairing wiring, clear the code and perform a misfire monitor drive cycle, because P1359 may not reset immediately if the fault was intermittent.

Can I keep driving with P1359?

You can usually drive short distances to a repair shop if the engine runs smoothly and the check engine light is steady, but avoid heavy acceleration or towing. If the light is flashing 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 Ford vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.