Fuel Pump Control Circuit Open
The P0627 code indicates an open or malfunction in the fuel pump control circuit. The powertrain control module (PCM) monitors the voltage and current in the fuel pump driver circuit. When the PCM detects an open circuit, short, or excessive resistance, it sets this code. This can prevent the fuel pump from operating, leading to engine stalling, no-start conditions, or poor performance.
1. Most Common Causes
- Faulty fuel pump relay with burned or pitted contacts
- Blown fuel pump fuse
- Open or short circuit in the control wiring
- Corroded, bent, or loose electrical connectors
- Defective fuel pump driver module (FPDM)
- Internal PCM/ECM failure (rare)
2. Symptoms You Will Notice
- Engine cranks but does not start
- Engine stalls shortly after starting
- Loss of power under load
- Check Engine Light illuminated
3. Step-by-Step Diagnosis
Step 1: Check fuel pump fuse and relay; replace if blown.
Step 2: Test fuel pump power and ground at the pump connector using a multimeter.
Step 3: Inspect wiring and connectors for damage, corrosion, or breaks.
Step 4: Test fuel pump driver module if equipped.
Step 5: If all else is good, replace the fuel pump.
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, potentially leaving you stranded or causing an accident.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, depending on the root cause and labor rates.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.