P0562 fault code: low system (battery) voltage
Plain-language definition
System Voltage Low
What does it mean?
The car's electrical system is powered by the battery when the engine isn't running and by the alternator when it is; the alternator also charges the battery. The engine computer and the other modules need a specific voltage range to work properly, so the engine computer constantly measures its own supply voltage.
If the voltage stays below the engine computer's lower limit for a set time, P0562 is stored. The code often points to a weakened battery or an alternator that isn't charging enough; sometimes it comes from nothing more than a loose or corroded connection. It may also have been left behind as a past record from a time when the battery was fully drained or the car was jump-started.
You may notice the starter struggling, dim headlights and interior lights, the battery warning light coming on or the start-stop system not working. Low voltage can also cause seemingly unrelated codes in other modules, such as communication codes. The 2dakika report may also show the battery voltage; when the scan is done without the engine running, this value reflects the battery's state at that moment, not the charging system.
How serious is it?
It's rated Warning, but if the low voltage continues, the battery can drain completely and the car may not start. Codes stored by other modules while the voltage was low should also be looked at together with this problem.
Severity is a guide; if the warning light is flashing or you notice symptoms while driving, have the car checked at a workshop.
Common general causes
- A weak battery, or one at the end of its life
- The alternator or voltage regulator not producing enough charge
- A loose, slipping or broken alternator belt
- Loose or corroded battery terminals, or a problem with the ground connection
- Something draining the battery while the car is parked (parasitic drain)
- Less often, a wiring, fuse or relay problem in the engine computer's power supply circuit
The list shows general causes; a workshop finds the actual cause on your car with a check.
Definitions by make
Some manufacturers record the same code under their own wording:
- Isuzu
- PCM or TCM constant power supply voltage low
Related codes
How does it appear in the 2dakika report?
System Voltage Low
If the code is read as a confirmed (stored) fault, the report shows it with the "Warning" severity; in pending or past records, codes that don't request the warning light and aren't critical appear as "Info". If the engine computer stored them, the conditions when the fault was recorded (engine temperature, rpm, speed) are shown too.
Read this code with the OBD-X1, and clear it from the app after the repair.
Clearing the code doesn't fix the fault; if the problem persists, the code comes back.