Fuel and air

P02FD — Cold Start Fuel Injection Control Circuit High

Severity: medium Drive with care, to a shop

What P02FD means

The cold start injector adds extra fuel in cold conditions to help the engine start, and the ECM monitors its control circuit. P02FD sets when the circuit voltage is higher than expected. Typical reasons are a wiring or connector fault, a failed injector, or, rarely, a problem inside the ECM.

Symptoms

  • Check Engine light is on
  • Hard starting in cold weather
  • Rough idle during warm-up
  • Hesitation or misfire feel on a cold start
  • Increased fuel consumption on a cold engine

Possible causes

  1. Damaged wiring or connector in the cold start injector circuit (open, corrosion, short to power)
  2. Failed cold start injector (open or damaged coil)
  3. Poor or missing ground in the control circuit
  4. Blown fuse or faulty relay feeding the circuit
  5. ECM fault or internal driver failure (uncommon)

How to diagnose

  1. Scan for codes, note freeze frame data and look for other fuel system codes
  2. Inspect the injector harness and connector for corrosion, chafing, melted insulation or loose pins
  3. Unplug the connector and check power and ground with a multimeter, following the vehicle's wiring diagram
  4. Measure injector coil resistance and compare it with factory specs
  5. Test the control wire between the ECM and injector for continuity and for shorts to power
  6. Check the related fuse and relay
  7. If wiring and injector are fine, test the ECM and check for software updates
  8. Clear the code and retest with a cold start to see if it returns

Common fixes

  • Repair or replace damaged wiring and connectors
  • Replace the cold start injector
  • Replace the faulty fuse or relay
  • Update ECM software or replace the ECM if confirmed faulty

Questions and answers

What does P02FD mean?

It means the ECM sees a high signal in the cold start injector control circuit. Most often this comes from wiring problems or a bad injector.

Can I drive with P02FD?

Usually yes, but expect possible hard starts in cold weather and rough running during warm-up. Do not put off diagnosis for long.

How do I fix P02FD?

Check the injector wiring, connector, power and ground first, then measure the injector resistance. Repairing the harness or replacing the injector fixes most cases.

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.