KlaroFault codeP0561
MODERATESystem Voltage Unstable
What this code means
System Voltage Unstable.
P0561 is a generic code: it means the same thing on every make. P0561 belongs to family P05xx — Idle speed and vehicle speed control. Its page explains how to read a code and groups all its codes by part.
System voltage
The control unit monitors the voltage of the electrical system it is fed by. A voltage too low or too high disturbs the sensors and the actuators, so it records these codes and may disable some functions.
What you notice
Hard starting, warning lights, electrical functions that misbehave; a battery that goes flat.
How to check it
Klaro shows the control module voltage: about 12.4 to 12.7 V with the engine off, 13.5 to 14.7 V with the engine running. A low value running points to the alternator or its belt; a low value at rest, to the battery. Check the battery terminals and the ground straps, whose corrosion causes many of these codes.
Watch it live in Klaro
With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:
- Control module voltage
What to do
Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.
Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →
How to read this code
- PPowertrain
- 0standardised code
- 5Idle speed and vehicle speed control
- 61P0561
