P1429Brake vacuum pump control: open circuit

• Volkswagen group code · Engine

How the car detects it

The circuit the engine computer uses to switch the electric brake vacuum pump is open. Braking still works, but the pedal can feel harder if the brake servo lacks vacuum.

What you may notice

• Warning light possible
• Harder brake pedal

Likely causes

• PossibleWiring or connector to the vacuum pump
• PossibleFuse or relay
• RareVacuum pump

Sources

• static.nhtsa.gov › MC-10172585-0001.pdf · official document

Backed by an official manufacturer document.

From Obdaryn's Volkswagen group pack, exactly as the app shows it, with the public sources above. Guidance only; confirm with a workshop.