P0561: the electrical system voltage keeps jumping around
The engine control unit constantly checks the voltage on the car's electrical system, the same supply the battery and the charging system share with almost every other component in the car. This code means that voltage isn't staying steady: it's moving around more than the computer expects, rather than settling too high or too low in one direction. Because so many sensors and modules rely on a steady voltage to give an accurate reading, an unstable voltage can make otherwise unrelated systems behave oddly at the same time.
You might notice
- The engine warning light comes on, sometimes alongside other warning lights
- Electrical items such as lights or the infotainment screen may flicker or reset
What the code itself says
P0561 is a powertrain (engine, gearbox and drive system) code, and the 0 after the letter means it is a generic code with a standard meaning.
Grouped here as: Charging and system voltage — System voltage and charging. That grouping is ours, to help explain the code. The code's official family is the letter at the start.
This page is generic. Your car isn't.
A code on its own only tells you what the sensor saw, not what's actually wrong — and that changes next to your other codes. Read this one together with the rest of your scan and we'll work out what's really going on.
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