The P0628: Fuel Pump ‘A’ Control Circuit Low code indicates that the control module has detected a low voltage in the fuel pump ‘A’ control circuit. This can be caused by a faulty fuel pump control circuit, low voltage in the circuit, or wiring issues, which can lead to improper fuel delivery and engine performance problems.
P0628 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0628: Fuel Pump ‘A’ Control Circuit Low |
| Is it serious? | Yes, as it can lead to fuel delivery problems and affect engine performance. |
| Possible causes | – Faulty fuel pump control circuit – Low voltage in circuit – Wiring issue |
| How to diagnose? | – Test fuel pump control circuit for voltage – Inspect wiring and connectors – Replace fuel pump or control circuit if necessary |
P0628 Meaning
The P0628 code indicates that the control module has detected lower-than-expected voltage in the fuel pump control circuit. This circuit is responsible for controlling the fuel pump, which supplies fuel to the engine. If there is a low voltage issue, it can lead to insufficient fuel pressure and may cause engine misfires, stalling, or a failure to start.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional codes related to the fuel system or electrical issues. | OBD-II Scanner |
| Test the Fuel Pump Control Circuit for Voltage | Use a multimeter to check the voltage in the fuel pump control circuit to ensure it is receiving the correct voltage. | Multimeter |
| Inspect Wiring and Connectors | Inspect the wiring and connectors linked to the fuel pump control circuit for damage, loose connections, or corrosion. | Flashlight, Multimeter |
| Test the Fuel Pump | If the control circuit appears fine, test the fuel pump itself to verify it is operating within specifications. | Diagnostic Tool, Multimeter |
| Replace the Fuel Pump or Control Circuit if Necessary | If the fuel pump or control circuit is faulty, replace the necessary components to restore proper fuel delivery. | Replacement Fuel Pump/Parts |
| Clear the Code and Test | After repairs, clear the code using an OBD-II scanner and test the vehicle to ensure that the fuel system operates correctly. | OBD-II Scanner, Vehicle Manual |
I test OBD-II scanners and make DIY Engine diagnostics guides to help you solve your car problems without having to depend on the mechanic. A lot of them will try to scam you or are just no help at all. About Juraj Lukacko