P0562: System voltage low
The supply voltage seen by the engine computer is too low.
Updated
What P0562 means
The engine computer watches its own supply voltage. When it stays below the limit for a while, it stores P0562.
Read My Car shows the battery voltage in live data, if your car reports it, and the terminal’s ATRV command shows the voltage the adapter measures at the OBD2 socket.
P0560, P0561 and P0563: other system voltage faults
P0560 is the general system voltage fault, P0561 a voltage that jumps up and down, often from a loose or corroded connection, and P0563 a voltage that’s too high: the charging system is overcharging. The checks start in the same place, the battery, its connections and the alternator. P0563 has its own driving advice, below.
P0560: System Voltage
The supply voltage seen by the engine computer is outside its normal range: too low, too high or unsteady.
Common causes: weak battery, failing alternator or voltage regulator, poor battery or earth connection.
P0561: System Voltage Unstable
The supply voltage seen by the engine computer is unstable: it jumps up and down.
Common causes: loose or corroded battery or earth connection, failing alternator or voltage regulator, weak battery.
P0563: System voltage high
The supply voltage seen by the engine computer is too high: the charging system is overcharging.
Common causes: faulty alternator or its voltage regulator, poor earth or wiring connection in the charging circuit, fault in the charging control, on cars where a computer controls the alternator.
Driving: Probably OK to drive short-term, but have it checked soon: too high a voltage can damage the battery and electronic parts. If the battery smells of rotten eggs, hisses or looks swollen, stop when it’s safe to do so, switch the engine off and keep away from it.
Can I keep driving?
Check soon
Probably OK to drive short-term, but have it checked soon. If the battery warning light is on as well, the alternator may not be charging: the car can stop once the battery runs flat, so drive only as far as you need to.
General guidance based on the code alone, not on the car’s actual condition. If in doubt, stop and ask a mechanic.
Low voltage can make other control units misbehave and store codes of their own, and a car with a failing alternator can stop once the battery runs flat.
Symptoms
- Slow cranking, or the engine won’t start.
- Dim lights, or a battery warning on the dashboard.
- Other, unrelated-looking fault codes from several modules.
Common causes
- Weak battery. Old batteries lose capacity, especially in the cold.
- Failing alternator. With the engine running, the voltage should rise above the engine-off value, at least just after starting. If it never does, the alternator may not be charging.
- Poor battery or earth connection. Loose or corroded battery clamps and earth straps drop the voltage.
How to fix P0562
- Check the battery clamps and the earth straps: clean, tight and free of corrosion.
- Compare the voltage with the engine off and running. On many cars a charging system shows roughly 13.5 to 14.5 V with the engine running; cars with smart charging or start-stop can show less at times, so a single low reading isn’t proof of a faulty alternator.
- Have the battery tested, and charged or replaced if it’s weak.
- Have the alternator and its wiring checked if the voltage doesn’t rise with the engine running.
FAQ
Can I drive with P0562?
Probably for a short time, but have it checked soon. If the battery warning is on as well, the alternator may not be charging: the car can stop once the battery runs flat, so drive only as far as you need to.
Is a too-high voltage (P0563) worse?
It can be: overcharging can damage the battery and electronic parts. If the battery smells of rotten eggs, hisses or looks swollen, stop when it’s safe to do so, switch the engine off and keep away from it.
Should I clear the other codes too?
Fix the voltage first, then read the codes again. Codes that low voltage caused often don’t come back once the supply is right; the ones that do need their own look.