Fuel Pump Secondary Circuit/Open
The P023F code indicates a fault in the secondary circuit of the fuel pump, typically referring to the control circuit from the PCM to the fuel pump relay or the pump itself. This can be caused by an open circuit, short, or malfunctioning component, leading to insufficient fuel pressure and potential engine performance issues.
1. Most Common Causes
- Open circuit in the fuel pump power or ground wiring
- Open fuel pump motor winding (internally damaged pump)
- Corroded, loose, or disconnected connectors at the pump or control module
- Internal failure of the pump driver in the PCM/FPCM
- Blown fuse or defective fuel pump relay
- Faulty fuel pump control module (FPCM) if equipped
2. Symptoms You Will Notice
- Engine cranks but does not start
- Loss of power or hesitation during acceleration
- Check Engine Light illuminated
- Fuel pump not priming when key is turned on
3. Step-by-Step Diagnosis
Step 1: Check for fuel pump prime by listening for a 2-second hum when turning key to ON position.
Step 2: Use a multimeter to test voltage and ground at the fuel pump connector; should see battery voltage during prime.
Step 3: Inspect fuel pump relay and fuse; swap relay with a known good one if possible.
Step 4: Check continuity and resistance in wiring from PCM to relay and pump; repair any opens or shorts.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The vehicle may stall or fail to start, leading to a dangerous situation.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, but can be higher if the fuel pump module needs replacement.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.