P0628 Generic (SAE) Basic entry

Fuel Pump 'A' Control Circuit Low

Updated 2026-10-02 · Computer & output circuits

Severity

Medium

Typical repair cost

40 – 350 EUR

System

Powertrain

What it means

P0628 is stored when the engine control module measures a voltage in the Fuel Pump 'A' Control circuit that stays below the expected minimum. In practice this points to a short to ground, a damaged wire or a failed component rather than a mechanical problem.

This entry is compiled automatically from the standard definition and typical diagnostic practice for this type of fault. A detailed, reviewed article is in preparation.

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Symptoms

Check engine light on
Engine may not start or runs in limp mode
Several unrelated codes stored at once
Erratic gauge or warning light behaviour

Common causes

Damaged, chafed or corroded wiring in the Fuel Pump 'A' Control circuit
Corroded, loose or water-damaged connector terminals
Failed Fuel Pump 'A' Control component (sensor, solenoid or actuator)
Poor ground connection for the module or component
Faulty control module driver (rare, confirm all else first)

How to diagnose

Read freeze frame data and note when the code set (cold start, under load, after rain)
Inspect the Fuel Pump 'A' Control connector for bent pins, corrosion and water; wiggle the harness with the engine running and watch live data
Measure supply voltage and ground at the connector with the key on
Check the signal wire for shorts to ground or battery and for continuity to the control module
Test or substitute the Fuel Pump 'A' Control only after wiring and connectors are confirmed good
Clear the code and complete a drive cycle to confirm the repair

Frequently asked questions

Can I keep driving with P0628?

Usually yes for a short time, but expect reduced performance or higher fuel use. Have it diagnosed within a few days.

Will clearing P0628 fix it?

No. Clearing only erases the stored code; it returns as soon as the monitor runs again unless the cause is repaired.