P06EC

What it means

P06EC means the fuel injector control module, a separate driver module used on some engines, has told the main engine control unit to switch on the malfunction indicator lamp (MIL). The main ECU has not found the fault itself. It is acting on a request received over the vehicle network. The real fault is normally stored as another code in the injector control module.

Symptoms

• Engine management warning light (MIL) on
• Rough running or misfire, if an injector fault is behind the request
• Reduced power or limp mode on some vehicles
• Hard starting or extended cranking
• Poor fuel economy
• Other fuel injector or communication codes stored

Possible causes

• Fault inside the fuel injector control module's own monitoring, such as an injector circuit, driver or internal fault, which has set its own codelikely
• Wiring or connector faults on injector circuits (open circuit, short or high resistance) feeding the injector control modulelikely
• Faulty fuel injector (electrical or mechanical) detected by the injector control modulepossible
• Poor power supply or earth to the injector control module, including low battery voltagepossible
• Network communication fault between the injector control module and the engine control unitpossible
• Outdated or faulty software in the injector control module or engine control unit, where the manufacturer has documented thisrare
• Internal failure of the injector control modulerare

How to diagnose

1. Read all stored and pending codes from every module, including the injector control module, and note which codes appear alongside P06EC.
2. Record the freeze frame data and check the conditions when the code set (engine speed, load, temperature, battery voltage).
3. Check battery condition and charging voltage, as low voltage can trigger injector driver faults and network errors.
4. Visually inspect the injector wiring, injector control module connectors, power feeds and earths for damage, corrosion, chafing, moisture or loose pins.
5. Follow the manufacturer's diagnostic procedure for the injector-specific code stored in the injector control module, as the procedure depends on the model and engine.
6. Test injector resistance and circuit continuity against the manufacturer's specification, and check for shorts to earth or supply.
7. Check network communication between modules and look for any communication or lost-signal codes.
8. Check for published software updates or technical bulletins for the module and engine.

How to fix

• Repair or replace damaged wiring, connectors or terminals found on the injector or module circuits.
• Replace any injector confirmed faulty by electrical or mechanical testing.
• Restore good power and earth connections to the injector control module and correct any battery or charging problem.
• Repair network wiring or resolve the communication fault that interrupts messages between modules.
• Update the module software only where an outdated or faulty calibration is a documented cause, and replace the injector control module only after other causes are ruled out.

Can I keep driving?

Nearby codes

• P06EBGenericNOx Sensor Processor Performance Bank 1 Sensor 2
• P06EDGenericEngine RPM Output Circuit Low