Power Supply Voltage Low
The system detects that the power supply voltage is below the acceptable range.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The power supply to the system is lower than it should be, typically below 9 volts. This can happen if there's a weak battery, poor connections, or issues with the power supply circuit.
What the computer is actually seeing
The computer monitors battery voltage and sees a reading lower than 9 volts, which triggers this code.
What a healthy reading looks like
Battery voltage should generally be between 12.4 to 14.7 volts when the engine is running.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the battery voltage with a multimeter. Expected: 12.4-14.7V. - If voltage is low, charge or replace the battery.
- 22. Inspect battery terminals for corrosion or looseness. - Clean and tighten if necessary, then retest voltage.
- 33. Test the alternator output voltage at the battery while the engine is running. - Expected: 13.5-14.7V. If low, check the alternator.
- 44. Check wiring and connections along the power supply circuit for damage or wear. - Repair any found issues before clearing the code.
Common causes
- Weak battery
- Corroded or loose battery terminals
- Faulty alternator
- Damaged wiring or connectors in the power supply circuit
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe to drive short distances, but address the issue soon to avoid battery failure.
Will this code come back after I clear it?
If the underlying issue isn't fixed, the code is likely to return.
Why does this code pair with other power-related codes?
These codes often share problems related to voltage supply, such as battery or alternator issues.
Working a real vehicle right now?
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