P2306

Code

LAND ROVER P — Powertrain

Primary control of ignition coil C - low circuit

Brand: LAND ROVER

Type: P — Powertrain

Views: UK: 19 EN: 47 RU: 33

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Page language: EN

Causes

Open or shorted wiring in the coil C primary control circuit
Poor or corroded connector at the ignition coil or ECM/PCM
Faulty ignition coil C (internal primary short or open)
Faulty ignition driver transistor inside the ECM/PCM
Poor battery/charging system voltage or a weak ground connection
Aftermarket components or recent repairs with incorrect wiring

Symptoms

Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
Rough idle or engine runs unevenly on start-up
Single-cylinder misfire or intermittent misfire (may set P030x codes)
Reduced engine power, hesitation or poor acceleration
Hard starting or extended cranking time
Poor fuel economy and increased emissions

What to check

Retrieve freeze-frame and all stored/related codes with a scan tool; note ignition event and engine speed when code set
Visually inspect coil C connector, wiring harness and ECM connector for damage, corrosion, loose pins or repairs
Check battery voltage and battery/engine ground connections
Backprobe coil C control pin while cranking/idle with a lab scope or multimeter (observe commanded signal)
Compare coil C behavior with other coils by swapping coils (if coils are identical) to see if the fault follows the coil
Measure coil primary and secondary resistance and compare to specification

Signal parameters

Expected idle/crank behavior: control circuit normally rests at ~12 V (supply) and the ECM switches the circuit to ground when firing, producing pulsed voltage between ~0–12 V
Typical primary pulse frequency: proportional to engine rpm (pulses per ignition event)
Primary coil resistance (typical): low ohm range (consult vehicle-spec service data)
Secondary resistance: high kΩ range (consult vehicle-spec service data)

Diagnostic algorithm

Confirm code and any related codes (P030x, P035x). Note freeze frame data.
Check battery state of charge and vehicle grounds; correct any low voltage or poor ground first.
Perform visual inspection of coil C connector, wiring, and nearby harness for damage or corrosion.
Backprobe coil C control pin with a multimeter or oscilloscope while cranking/idle: verify voltage pulses (12 V to ~0 V switching). If no pulse, suspect wiring or ECM driver.
Disconnect coil C and measure continuity between coil control terminal and ECM driver pin; check for unintended short to ground or battery.
Measure primary resistance of coil C (compare to spec). If out of range, replace coil and retest.
Swap coil C with another identical coil; if the code moves to the other cylinder, replace the coil. If it stays, focus on wiring/ECM.
If wiring is open/shorted, repair or replace harness/connector and recheck. If wiring is good but no driver output, test/replace ECM following manufacturer procedures.
After repairs, clear codes and perform test drive to confirm the fault does not return. Document findings and parts replaced.

Likely causes

Damaged/shorted harness to coil C (abrasion, chafing, rodent damage)
Corroded or loose coil connector pins or ECM connector pins
Failed ignition coil primary winding or internal electronics
ECM/PCM driver transistor failure
Low battery voltage or high-resistance ground causing incorrect signal levels

Fault status

⚠️ Status

ECM detected low voltage on the primary control circuit for ignition coil C. MIL set; fault may be intermittent or continuous. Additional misfire or coil circuit codes may be present.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours

Repair manuals

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Browse 413 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

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P2306 — Primary control of ignition coil C - low circuit