P0556 — OBD-II trouble code

A generic powertrain OBD-II trouble code. Below are the vehicles and failure patterns where owners report it, drawn from NHTSA complaints.

In ProblemsByVin's analysis of the NHTSA owner-complaint record, owners cite P0556 across 9 vehicle failure patterns. Diagnostic codes in complaints are reported by owners and are unverified — they point to where this code shows up, not a confirmed diagnosis. Open a page below for the full pattern (symptoms, mileage, repair costs owners cite).

Vehicles where owners report P0556 9 patterns

2023 Chevrolet Traverse

electrical — Alternator failure with charging system loss

2020 Chevrolet Equinox

brakes — Brake vacuum pump failure

2020 Chevrolet Malibu

brakes — Brake vacuum pump failure

2020 GMC Terrain

brakes — Brake Vacuum Pump Failure

2019 Chevrolet Malibu

powertrain — Transmission loss of power and delayed acceleration

2019 Chevrolet Malibu

brakes — Brake vacuum pump failure with hard pedal

2017 Chevrolet Malibu

brakes — Brake Vacuum Pump Failure

2017 Ford F-150

brakes — Master Cylinder Failure

2016 Chevrolet Malibu

brakes — Brake Booster / Vacuum Pump Failure

Codes are pulled from what owners wrote in their NHTSA filings — they're allegations, not a shop diagnosis. Always confirm with a live scan. Browse all diagnostic codes →