Powertrain, generic (extended)

P2306 Ignition Coil C Primary Control Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With P2306 the engine module has seen the output for coil C, cylinder 3 at GM, Saab and VW, dragged down to ground. Ford explains where such a fault can sit on engines whose coils carry their own driver: the coil-driver chip in the PCM watches current and voltage at its output, so the culprit may be the PCM, the harness, the plug-in connection at the coil or the driver electronics inside the coil – but not the windings, which only the misfire monitor sees. The check is continuous, needs 200 rpm, positive torque and 11–16 V and decides within 1 s. VW's 2014 tables set the low code when the line draws more than 24 mA. Saab's Trionic 8 pairs cylinder 3 with cylinder 1 for its combustion signal. FCA lists P2306-00 for 2023 Alfa Romeo Stelvio 2.0 turbo engines fixed by PCM software.

Likely causes

Driver electronics inside coil C defective
Coil C control wire grounded through chafing or a pinched harness
Corroded or bent pins at the coil C connector
PCM output or software (FCA 2023 reflash)

Symptoms

  • Check engine light on
  • Misfire on cylinder 3
  • Uneven idle, possibly cylinder shut-off

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–400
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

ignition coilcoil driverignition wiring

Related codes

P2307P2308P0353P2303P0303

References: newtonnet.co.uk, static.nhtsa.gov, saabwisonline.com, static.nhtsa.gov.