P0563: System Voltage High
GarageDex's OBD-II reference explains that code P0563 means "System Voltage High" - The computer sees charging voltage above normal - usually an over-charging alternator/voltage regulator.
Moderate - drivable, but don't put it off
Drivable short-term, but overcharging can cook the battery - get it checked.
Symptoms
- Overly bright/flickering lights
- Battery warning
- Shortened battery life
Common causes (most to least likely)
- Faulty voltage regulator / alternator overcharging
- Poor ground causing false high reading
- Wiring fault
How to fix P0563
- Measure charging voltage (should be ~13.5-14.7V)
- Check grounds
- Replace the alternator/regulator if overcharging
Guidance only - confirm the cause with a scan before replacing parts. Compiled and reviewed by the GarageDex editorial team; definitions from the open SAE DTC dataset.
Tools & parts for P0563
Confirm the cause before you buy anything - a code points to a system, not a guaranteed part. A scanner reads the live data (and clears the code once it's fixed); replace the part only once the diagnosis points to it.
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Frequently asked
What does the P0563 code mean?
GarageDex's OBD-II reference explains that code P0563 means "System Voltage High" - The computer sees charging voltage above normal - usually an over-charging alternator/voltage regulator.
What are the symptoms of P0563?
Common symptoms: Overly bright/flickering lights; Battery warning; Shortened battery life.
What causes a P0563 code?
The common causes, most to least likely: Faulty voltage regulator / alternator overcharging; Poor ground causing false high reading; Wiring fault.
Is it safe to drive with a P0563 code?
Drivable short-term, but overcharging can cook the battery - get it checked.
How do I fix a P0563 code?
Measure charging voltage (should be ~13.5-14.7V) Check grounds Replace the alternator/regulator if overcharging Confirm the cause with a scan before replacing parts.