P0562 — System Voltage Low (MG Context)
Standard meaning: the ECU measured system voltage below its calibrated threshold for long enough to log a fault. On an MG, P0562 deserves special attention, because a low-12V pattern is one of the best-documented issues across the range: flat auxiliary batteries and 12V charging faults are recurring owner reports on the ZS EV, the MG4 and the HS — and in several documented cases the root cause was software, not the battery.
What it means on your MG
| If you drive… | The documented pattern | First move |
|---|---|---|
| ZS EV / MG4 | The car may stop topping up the 12V battery from the traction pack (“12V Battery Charging System Fault” reports), or drains it while parked. | Ask the dealer for the latest software and a 12V health test together — owners report replacing the battery alone often doesn’t end it. |
| HS (incl. 2025–26 PHEV) | Documented drain cases traced to the infotainment backlight staying on after locking; root cause reported as firmware. | Same: software first, then battery. |
| Petrol ZS / MG3 (older fleet) | No systemic pattern documented — on an ageing car this is usually a genuinely tired battery, corroded terminals or a failing alternator/belt. | Battery age and terminal check, then charging-voltage test at a workshop. |
Pattern evidence: our per-model problems research (owner-community threads 2020–2026, documented in each model’s extraction record). Code definition per SAE J2012.
Safe owner checks — before any parts are bought
- Battery age (label/invoice) — most 12V batteries are consumables at 4–6 years.
- Terminals clean and tight (engine off, 12V system only — never touch orange high-voltage cabling on EVs/hybrids).
- Did the code appear after the car stood unused for days? That points at drain, not charging.
- Any accessories wired in (dashcam hardwire kits are a classic parasitic drain)?
When it’s a workshop job
Charging-system voltage tests, parasitic-drain measurement, and on EVs/hybrids anything involving the DC-DC converter that charges the 12V battery from the traction pack — that last one is high-voltage-adjacent and strictly dealer/qualified-technician territory. If P0562 returns after a healthy battery and current software, stop guessing and book it in with the freeze-frame data intact.