Fuel and air

P02FC — Cold Start Fuel Injection Control Circuit Low

Severity: medium Drive with care, to a shop

What P02FC means

The engine control unit operates a cold start injector or valve that enriches the fuel mixture when the engine starts cold. P02FC sets when the voltage in that control circuit is lower than expected, which can come from an open circuit, a short to ground or a failing injector. Exact definitions vary by manufacturer, so check the wiring diagram for your vehicle.

Symptoms

  • Check engine light on
  • Hard starting when the engine is cold
  • Rough idle during warm-up
  • Increased fuel consumption
  • Hesitation when pulling away cold

Possible causes

  1. Damaged wiring or poor connection at the cold start injector connector
  2. Faulty cold start injector or control valve
  3. Control wire shorted to ground
  4. Corroded or water-contaminated connector
  5. Failed driver inside the ECU (uncommon)

How to diagnose

  1. Scan all codes and record the freeze frame data
  2. Inspect the injector harness and connector for damage, corrosion and chafing
  3. Measure the injector coil resistance and compare it to the specification
  4. Check for power at the connector with the ignition on
  5. Test the control wire to the ECU for opens and shorts to ground
  6. Check injector operation with a scan tool or a noid light
  7. If wiring and injector are good, inspect the ECU connector and driver
  8. Clear the code and confirm it does not return after a cold start

Common fixes

  • Repair or replace damaged wiring and connectors
  • Replace the cold start injector or valve
  • Clean the terminals and seal the connector against moisture
  • Repair, reflash or replace the ECU if it has an internal fault

Questions and answers

What does P02FC mean?

The ECU sees too little voltage in the cold start injector control circuit. The usual causes are wiring, a connector or the injector itself.

Can I drive with code P02FC?

Usually yes, especially in warm weather, but cold starts may get worse. Diagnose it soon so you are not stranded by a no-start.

How do I fix P02FC?

Start with the injector wiring and connector, then test the injector resistance and power supply. If those are fine, suspect the ECU.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.