The Lemon IndexThe brake booster vacuum reading doesn't make sense.
Stop and fix now. Don't put it off. This can affect safety, stall the car or cause expensive damage.
Failed booster pressure sensor. Then: vacuum leak; weak vacuum pump.
Owners named P0556 in 13 complaints to the U.S. government, most often on the Chevrolet Malibu.
Cars owners report it on
Complaints that name P0556, by model. Raw counts, not a failure rate: popular models get more complaints.
Years owners report it on most: 2020 GMC Terrain · 2019 Chevrolet Malibu
The details
What P0556 means
The brake booster vacuum reading doesn't make sense. Brakes may feel harder to press.
Can I drive with P0556?
Stop and fix now. Don't put it off. This can affect safety, stall the car or cause expensive damage.
100% of the owner complaints that name P0556 also say the car brakes or ABS act up. A complaint can describe more than one problem, so this doesn't prove the code caused it.
Common causes of P0556
- Failed booster pressure sensor
- Vacuum leak
- Weak vacuum pump
A shop should confirm the cause with a scan and tests before replacing parts.
What owners describe
- Brakes or ABS act up: 100% of complaints
- Loses power or goes into limp mode: 23% of complaints
Share of complaints naming the code whose text also mentions each problem.
Model years that report P0556 most
2020 GMC Terrain (3), 2019 Chevrolet Malibu (2).
Related codes
P0562 P0571 P052E P0524 P0523 P0521 P0520 P051B
Quick answers
What does P0556 mean?
Brake Booster Pressure Sensor Circuit Range/Performance. The brake booster vacuum reading doesn't make sense. Brakes may feel harder to press.
Can I drive with P0556?
Stop and fix now. Don't put it off. This can affect safety, stall the car or cause expensive damage.
What causes P0556?
Failed booster pressure sensor; Vacuum leak; Weak vacuum pump.
Counts: NHTSA owner complaints whose text names P0556. A complaint is an owner's report, not a diagnosis. Meanings: the standard SAE J2012 definitions in our own words; manufacturer codes only where verified for that make. General information, not repair advice for your car.