P0628 Fault Code

Fuel Pump A Control Circuit Low

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0628 fault code indicates an issue with the fuel pump A control circuit exhibiting a low voltage condition. This problem typically arises when the fuel pump is not receiving sufficient voltage to operate effectively, potentially leading to engine performance issues or failure to start.

What are the symptoms of the P0628 code?

Drivers may experience a variety of symptoms associated with the P0628 code, such as:

• Engine cranking but not starting
• Intermittent engine stalling
• Decreased engine performance or acceleration issues
• Audible noise from the fuel pump
• Dashboard warning lights illuminated, particularly the check engine light.

What causes the P0628 code?

Several factors can contribute to the P0628 code, including:

• A defective fuel pump
• Poor wiring or connections in the fuel pump circuit
• A faulty fuel pump relay
• Issues with the vehicle's ECM or PCM that controls the fuel pump operation
• A blown fuse in the fuel pump circuit

How to fix P0628?

To resolve the P0628 code, the following steps are recommended:

1. Perform a visual inspection of the fuel pump wiring and connectors for signs of damage or corrosion.
2. Use a multimeter to test the voltage at the fuel pump connector to determine if it matches manufacturer specifications.
3. If there is low voltage, check the fuel pump relay and fuse for continuity and proper operation.
4. If the wiring is intact and the relay is functioning, consider replacing the fuel pump itself.
5. Clear the fault code and test drive the vehicle to see if the code reappears.