P1362

Code

Other P — Powertrain

Ignition Coil C Secondary Circuit Malfunction

Brand: Other

Type: P — Powertrain

Views: UK: 25 EN: 55 RU: 43

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Faulty ignition coil (coil C)
Worn, fouled or damaged spark plug or ignition boot
Damaged high-voltage lead or secondary wiring (arcing, cracked boot)
Poor connector contact, corrosion, or damaged wiring to the coil
Faulty ignition control driver in the ECM/PCM
Water, oil or carbon tracking causing secondary leakage/arcing

Symptoms

Check Engine Light (MIL) illuminated with P1362 stored
Rough idle or intermittent misfire
Loss of power, hesitation or poor acceleration
Reduced fuel economy
Noise such as popping/backfire in intake or exhaust
Misfire code(s) for the associated cylinder (may be present)

What to check

Retrieve freeze-frame data and all stored DTCs; note associated misfire counts and related codes.
Identify which physical cylinder is served by 'ignition coil C' per vehicle service manual.
Visual inspection of coil, boot, spark plug and surrounding area for cracks, oil, carbon or moisture.
Swap coil C with a known-good coil from another cylinder and see if the trouble follows the coil.
Inspect wiring and connector for corrosion, broken pins, burned insulation or poor fit; wiggle harness while observing live data.
Perform a plug check: remove plug, inspect electrode/gap, and swap or install a new plug if suspect.

Signal parameters

Primary coil resistance (typical range): approx. 0.4 – 2.0 Ω (varies by design) — consult OEM spec.
Secondary coil resistance (typical range): approx. 5 kΩ – 30 kΩ depending on coil design — consult OEM spec.
Primary driver signal: switching between ~0 V and battery voltage (≈12 V) at pulse rate matching ignition events.
Primary waveform: defined dwell (ECU grounds coil primary) followed by a rapid collapse on turn-off; collapse produces high secondary voltage (tens of kV).
No continuity or infinite resistance on secondary indicates open circuit; excessive low resistance indicates internal short.

Diagnostic algorithm

Read and record all codes, freeze-frame and live data. Confirm P1362 and identify which cylinder is 'coil C' from the service manual.
Perform a visual inspection: look for cracked boots, oil/fuel contamination, carbon tracking, or obvious wiring damage at the coil and plug.
Swap coil C with another cylinder's coil. If the fault moves with the coil, replace the coil. If it stays on the same cylinder, continue investigating wiring/ECU.
Inspect and/or replace the spark plug and boot for the affected cylinder. Ensure correct gap and proper seating.
Measure coil primary and secondary resistance with a multimeter and compare to OEM values. Replace if out of range or open.
Use a lab scope to verify ECU coil drive: confirm proper pulse voltage, dwell and clean collapse waveform. Look for missing pulses or erratic drive.
Check connector continuity and ground between coil and ECU. Backprobe connector while cranking to confirm switching and reference ground.
Test for secondary spark under load using an approved in-line spark tester or scope; inspect for arcing to ground or weakness.
Repair or replace damaged wiring, connector, coil, boot, or plug as indicated. If wiring and coil are good, evaluate ECU ignition driver circuits and ground integrity.
After repairs, clear codes, perform a road test and monitor live misfire counts and coil driver waveforms to verify the issue is resolved.

Likely causes

Damaged or failed ignition coil (most common)
Faulty or fouled spark plug/boot
Open/damaged secondary lead or poor connector/boot seating
Secondary arcing due to contamination or cracked boot
Intermittent wiring/connector fault between coil and ECU

Fault status

⚠️ Status

Ignition Coil C secondary circuit malfunction detected. Possible causes: failed coil, bad plug/boot, damaged secondary wiring, or faulty ignition driver. Verify coil output, wiring, and ECU drive signal.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours (depends on access, required tests and parts)

Repair manuals