MECU power supply, value
WARNING: This page is about a different car, the 2007 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.
Measurement range: 0 - 63 V
Normal range: 12.0 - 14.5 V
The value indicates the power supply to the central electronic module (CEM) when the diagnostic trouble code was generated.