System Voltage Low (P0562)
The P0562 code indicates that the vehicle's powertrain control module (PCM) has detected a system voltage below the specified threshold (typically below 10 volts for an extended period). This can be caused by a failing alternator, a weak battery, corroded or loose battery connections, or a faulty voltage regulator. The PCM monitors system voltage to ensure proper operation of sensors and actuators; low voltage can lead to erratic performance, dim lights, and potential stalling.
01. Most Common Causes
- Weak or dead battery
- Faulty alternator not charging properly
- Corroded or loose battery terminals or cables
- Faulty voltage regulator (often integrated into alternator)
- Excessive parasitic drain on the battery
02. Symptoms You Will Notice
- Battery or check engine light illuminated
- Dim headlights or interior lights
- Slow engine crank or no start
- Electrical accessories malfunctioning (e.g., power windows slow)
- Vehicle may stall or run poorly
03. Step-by-Step Diagnosis
Step 1: Use a multimeter to measure battery voltage with engine off (should be ~12.6V).
Step 2: Start engine and measure voltage at battery terminals (should be 13.5-14.5V if alternator is charging).
Step 3: Inspect battery terminals and cables for corrosion, looseness, or damage; clean and tighten as needed.
Step 4: Test alternator output and voltage regulator; replace if output is low or erratic.
Step 5: Check for parasitic drain by measuring current draw with ignition off (should be <50mA).
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with P0562 as low voltage can cause stalling, loss of power steering, and damage to electronic components. Have the vehicle towed to a repair shop.
How much does it cost to fix?▼
Costs vary: battery replacement $100-$200, alternator replacement $300-$600, terminal cleaning $50-$100. Diagnostic fee typically $50-$150.