P0351

Code

LAND ROVER P — Powertrain

Ignition Malfunction of the primary/secondary circuit of the coil A

Brand: LAND ROVER

Type: P — Powertrain

Views: UK: 17 EN: 29 RU: 90

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Page language: EN

Causes

Failed ignition coil (coil A)
Open or short in coil primary or secondary wiring
Corroded/loose connector or poor pin contact
Loss of power supply or ground to the coil
Faulty ignition control driver in the PCM/ECM
Damaged spark plug or spark plug boot creating abnormal load

Symptoms

Check Engine Light (malfunction indicator lamp) on
Misfire on the affected cylinder (rough idle, surge, vibration)
Reduced power and poor acceleration
Increased fuel consumption and emissions
Possible hard start or no-start if coil fails completely

What to check

Read and record DTC(s) and freeze-frame data with a scan tool
Check for accompanying misfire codes (P03xx) and cylinder ID to confirm affected cylinder
Visually inspect coil, connector, spark plug and lead for damage, carbon tracking or oil contamination
Backprobe coil connector to verify constant 12V (or battery voltage) supply and good ground when cranking
Measure coil primary resistance (with connector disconnected) and compare to specification/service manual
Measure coil secondary resistance (where accessible) and compare to spec

Signal parameters

Primary DC resistance (typical coil-on-plug range): ~0.2–2.0 Ω (check Land Rover service data for exact value)
Secondary resistance (typical): ~5 kΩ–15 kΩ (spec varies by coil type)
Supply voltage to coil: ~Battery voltage (11–14.5 V) with key on/crank
Primary driver behavior: switching pulses from PCM (square waveform) timed to engine speed; dwell time varies with engine conditions
Primary current: can be 1–8 A during dwell depending on coil design — measure with appropriate current probe/oscilloscope

Diagnostic algorithm

Retrieve freeze-frame and confirm occurrence conditions (engine speed, temperature, load).
Note any additional codes (misfire codes). Inspect spark plug, boot and coil visually for cracks, carbon tracking or oil contamination. Replace plug/boot if badly fouled.
With ignition OFF disconnect coil A connector; measure primary and secondary DC resistance per service manual. Compare values to Land Rover specs. If out of range, replace coil.
With harness connected, backprobe coil power lead (battery feed) to confirm battery voltage present with key ON. Check ground/return when cranking or commanding coil. Repair any open circuits.
Use a scan tool to command coil (if supported) while monitoring supply and control signal. Confirm PCM is providing a switching/control signal. If no control signal but wiring and supply are good, suspect PCM.
Swap coil A with another cylinder’s coil (if identical) and clear codes. If DTC follows coil, replace coil. If DTC remains on same cylinder, focus on wiring/PCM for that circuit.
Use an oscilloscope to inspect coil primary waveform during cranking/running to detect shorted turns, collapsed primary, excessive dwell, or no switching. Inspect secondary for expected spark pulse characteristics.
Inspect and test wiring harness for continuity and shorts between the coil driver circuit and ground/battery. Repair broken wires, corroded pins or damaged connectors.
After repairs, clear codes and road-test to confirm code does not return and misfire symptoms are resolved.
If all wiring, coil and spark components check OK but PCM shows no proper driver activity, consider PCM diagnosis/repair/reflash following manufacturer procedures.

Likely causes

Faulty coil-on-plug (COP) or coil pack for cylinder A
Damaged/shorted primary feed or driver circuit wiring
Corroded connector or poor ground at coil
PCM driver fault (less common)

Fault status

⚠️ Status

P0351 — Ignition Coil A Primary/Secondary Circuit Malfunction. The PCM detected an abnormal condition in the coil A circuit (open, short, intermittent, or out-of-spec coil performance). Further electrical and component tests are required to locate the fault.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-2 hours

Repair manuals

Manual library for LAND ROVER

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P0351 — Ignition Malfunction of the primary/secondary circuit of the coil A