P2309Ignition Coil D Primary Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2309 stands for a grounded control lead to coil D – cylinder 4, which on a four-cylinder engine is the last coil in the row. In 2023 FCA released bulletins 18-022-23 and 18-023-23 for the Alfa Romeo Giulia and Stelvio with the 280 hp 2.0 turbo: P2300-00, P2303-00, P2306-00 and P2309-00 could set together with an EVAP purge code, and the remedy was PCM software rather than parts. On Ford petrol engines of 2020–2023 the coil codes P2300 to P2310 are among the faults that block automatic engine stop-start. On Saab's LDK-engined 9-5 of 2010 the same code needs 4 s of continuous or 50 s of cumulative short and is Type B. When all four low codes appear at once, suspect software or a shared harness section before replacing coils.
- What you may notice
- Check engine light on
- Misfire on cylinder 4
- Auto stop-start no longer works (Ford)
- Reduced power
- Likely causes
- LikelyCoil D (cylinder 4) defective
- PossiblePCM software fault setting several coil low codes (FCA 2.0 turbo 2023)
- PossibleDamaged harness section carrying several coil lines
- RarePoor contact or moisture at the coil D connector
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.