P0563
System Voltage High
high
i Description
The ECU has detected that the system voltage has exceeded the normal operating range (typically above 16V). Overcharging can damage electrical components and the battery.
? Common Causes
- Faulty voltage regulator (usually built into alternator)
- Faulty alternator (overcharging)
- Poor ground connection causing voltage offset
- ECU misreading voltage (rare)
! Symptoms
- Check engine light
- Battery overheating or swelling
- Bulbs blowing frequently
- Electrical components failing prematurely
- Battery boiling
# Diagnostic Steps
- Test alternator output voltage (should not exceed 14.8V)
- Check voltage regulator
- Inspect ground connections
- Replace alternator if overcharging
⚙ Typical Fix
Replace the alternator/voltage regulator.
Parts Needed
Alternator, Voltage regulator
Estimated Cost
$200-$600
↔ Related Codes
Q Frequently Asked Questions
Drive directly to a mechanic. Overcharging will damage the battery (risk of swelling or leaking) and can blow expensive electrical components.
Alternator replacement: $200-$600 including labour. Some vehicles have a separate voltage regulator ($50-$150).
☞ Learn More
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