P0611Fuel Injector Control Module Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0611 concerns systems with a separate injector control module or injector driver stage. On GM's 6.6 L Duramax LB7/LLY the injector driver unit reports a microcontroller, monitoring or converter fault or a timeout to the engine module over CAN; the code sets after 30 of 50 checks at 125 ms with battery voltage of 10–18 V, and the lamp follows after two trips. On Ford's 6.0 L Power Stroke the injector module steps battery voltage up to about 48 V; Ford's bulletin requires it to stay above 45 V during the last 10 s of the injector prime, with the battery at 11.5 V or more – weak batteries strain and damage the converter. Newer Ford diesels check an internal reference measurement (0–3300 mV, 5 s). Results are hard or no starting, rough running and low power.
- What you may notice
- Hard or no start, especially when cold
- Rough running, misfires
- Lack of power
- Check engine light (GM after two trips)
- Likely causes
- LikelyFaulty voltage converter or driver stage in the injector module (Ford 6.0 L)
- LikelyLow battery voltage, weak batteries or poor ground
- PossibleCAN or supply line between engine and injector module disturbed
- RareFaulty module software (update available)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €300 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.