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DTC code page

P0629: Fuel Pump A Control Circuit High

Quick answer: The ECU sees the fuel pump A control circuit stuck high or higher than expected.

Drivers also search this fault as fuel pump A control circuit high, P0629 fuel pump control high, fuel pump A stuck high.

Severity: medium Family: powertrain Related paths: 10
Meaning

What P0629 usually means

P0629 is the control-circuit-high version of the pump A branch. It usually points to a short to power, feedback bias, or a control stage that remains energized when the ECU expects the circuit to drop. Unlike the low branch, this code can leave the system acting over-commanded or falsely reporting continued pump drive, which is why it often pairs with battery-drain, rich-restart, or key-off pump concerns more than pure crank-no-start complaints.

Fast triage

Start here before chasing parts

  • Scan first: save freeze-frame and pending codes before clearing anything.
  • Confirm the complaint: compare the stored code with current drivability symptoms.
  • Use context: trims, live data, and related codes usually narrow the fault faster than guesswork.
  • Work simplest to hardest: leaks, connectors, maintenance items, and known patterns before expensive components.
Initial checks

What to check first

  • Check whether the pump continues running after key-off or at times it should be inactive.
  • Inspect the relay or module output for a stuck-on condition before replacing the pump.
  • Watch for battery drain or fuel odor clues that support unwanted pump operation.
Driving risk

Can you keep driving?

P0629 may not strand the vehicle as quickly as the low or open variants, but it can create pump overrun, battery drain, and fuel-delivery behavior that should be corrected promptly.

Moderate urgency: This code often allows short-term driving, but the right fix usually comes faster when you diagnose it early instead of waiting for more codes.
Likely causes

Common causes behind this code

  • Short to power on the pump A control line
  • Fuel-pump control module output stuck on
  • Relay or transistor driver latched closed
  • Biased feedback circuit falsely reporting high command
  • Aftermarket wiring or previous repair error holding the circuit high

Cause phrases often tied to this code: short to power, stuck driver, relay welded, biased feedback, module fault.

Diagnostic order

Suggested workflow

  1. Confirm whether the control line or feedback stays high relative to commanded state.
  2. Check for short-to-power and relay or module output that remains energized.
  3. Compare scan-tool command with actual circuit voltage where supported.
  4. Inspect for aftermarket wiring or prior repairs that bypassed normal control.
  5. After repair, confirm proper key-off behavior and normal fuel-delivery operation.
Avoid guesswork

Common mistakes

  • Treating P0629 like a simple no-start code when the problem may be a stuck-on circuit instead.
  • Missing battery-drain evidence because the vehicle still seems to run well enough.
  • Replacing the pump rather than the control fault keeping it energized.
Repair path

Practical fix guidance

  • Repair the short-to-power, latched driver, or false-high feedback fault on the pump A control branch.
  • If the pump has been running at the wrong time, verify no secondary wiring or connector heat damage developed.
  • Recheck key-off current draw and command behavior after the repair.
Vehicle context

Affected brands in this MVP

Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.

Aliases and common searches

English phrases tied to P0629

Useful when the driver knows the wording but not the exact DTC yet.

  • fuel pump A control circuit high
  • P0629 fuel pump control high
  • fuel pump A stuck high
Related search intent

Queries this page can answer naturally

  • P0629 code meaning
  • what does P0629 mean
  • fuel pump A control circuit high symptoms
FAQ

Quick questions about P0629

Can P0629 make the fuel pump run after key-off?

Yes. A stuck-high control path or welded output stage can do exactly that.

Does P0629 always create high fuel pressure?

Not automatically. It names a control-circuit-high condition, though unwanted pump operation can affect pressure and restart behavior.

What is a common clue with P0629?

Battery drain or hearing the pump when it should be off is a strong real-world clue.