P0562 is the OBD-II code for System Voltage Low, which the powertrain control module sets when voltage stays too low while the engine runs. P0562 is a generic code, so its basic definition is shared across most manufacturers.
The causes range from a weak charging system and a worn battery to loose wiring and blown fuses. Check the battery and charging parts first, then confirm with voltage readings.
Battery and charging work can cause electrical shocks and burns. If you are unsure, have a qualified technician check the system.
P0562 Code Meaning: What System Voltage Low Tells You
P0562 means System Voltage Low, a generic OBD-II code that the powertrain control module sets when voltage drops too low while the engine runs.
Mechanicbase describes the trigger as voltage below 10.0 V for more than 60 seconds with the engine running. A brief dip does not meet that rule, so the code points to a sustained problem in the charging or battery circuit.
A healthy charging system with the engine running should read about 13.5 to 14.5 V. Kelley Blue Book gives a wider range of about 13.5 to 15 V. With the engine off, a healthy battery reads about 12.6 V, which is the reference point for a p0562 code check.
Common Causes of This Code
The listed causes of P0562 start with a faulty alternator or voltage regulator, then wiring problems, a worn battery and blown fuses.
- Faulty or broken alternator or voltage regulator
- Loose, corroded or defective wiring, including wiring between the alternator and the PCM
- High resistance in the battery cables
- Blown fuses
- A worn-out battery
- A large battery drain
- A faulty PCM, which is the least common cause
A bad battery and a bad alternator can produce similar voltage readings, so the causes are best separated with the tests in the diagnosis section below.
Symptoms You Might Notice
The most direct signs of P0562 are a check engine light and a battery or charging warning light, often with rough running or stalling.
- Check engine light, sometimes with a battery or charging warning light
- Rough idle
- Stalling or the engine shutting off
- Trouble accelerating
- Erratic shifting in automatic transmissions
- Reduced fuel economy
- Electrical functions failing, such as fuel injection or power steering
Mechanicbase also warns that a restart may fail after a stall, so a car that will not restart should be checked for this code. For a closer look at the battery itself, see the guide on how to use a battery tester.
How Serious Is This Code?
Treat P0562 as urgent: Kelley Blue Book calls it a pretty severe code and advises against driving the car until it is inspected.
According to Kelley Blue Book’s P0562 guide, the vehicle may stall at idle or shut off completely, and ABS or power steering may stop working. Mechanicbase rates the code as medium severity and warns that stalling in heavy traffic could cause an accident.
The two ratings disagree, so the cautious reading is the safe one. Avoid long trips and have the charging system checked soon.
If the warning appears while you are driving, move to a safe place to stop when you can. A car that stalls in traffic can leave you without power steering or ABS, so the stop itself is a safety step, not only a repair step.
How to Diagnose a P0562 Code
Read all stored codes first, then measure battery voltage with the engine off and running. A digital multimeter on your car is enough for both readings. A healthy system reads about 12.6 V off and 13.5 to 14.5 V running.
Measuring with the Engine Off
With the engine off, a battery in good shape reads about 12.6 V. A lower reading suggests a bad battery, so test the battery before blaming the alternator.
- Check the scanner for other trouble codes, since they may point to the same fault.
- Inspect the battery wiring and replace any damaged wires.
- Check connectors for looseness or corrosion, and clean corrosion with water and baking soda.
- With the engine off, measure battery voltage. About 12.6 V is normal.
- Start the engine and measure again. Expect about 13.5 to 14.5 V if the alternator is working.
- If you suspect a parasitic draw, watch battery voltage while pulling fuses one at a time to find the circuit.
| Check | Expected reading | What a problem looks like |
|---|---|---|
| Engine off | About 12.6 V | A lower reading suggests a bad battery |
| Engine running | About 13.5 to 14.5 V | Below 12 V suggests a charging problem |
| PCM trigger | Above 10.0 V | Below 10.0 V for more than 60 seconds sets the code |
Read the results together. A low reading with the engine off points to the battery. A normal reading with the engine off and a low reading with the engine running points to the charging side, which includes the alternator, the voltage regulator and their wiring. If both readings look normal but the code stays, the fault may come and go, so recheck the connections and review the other stored codes again.
A low-voltage condition can set this code in other modules too. GM bulletin PIT6347A, published in March 2025 covers the 2022 to 2025 Cadillac Escalade and Escalade ESV, Chevrolet Suburban and Tahoe, and GMC Yukon and Yukon XL. It says P0606 and P0562 set in the brake control module come from a low-voltage condition that is more common in cold weather and at a lower battery state of charge.
If normal diagnostics find no root cause, that bulletin tells technicians to test the battery and make sure the battery cables and fuse block connections are clean and tight. It also says to inspect the charging system and to check for aftermarket equipment that can draw down the battery, such as dash cameras and phone chargers, and a parasitic draw test.
What to Fix First
Fix the cause the tests point to. The listed causes include damaged wires, corroded connectors and blown fuses, so start with wiring and connections before you replace an alternator or regulator. If the tests do point to the alternator, the alternator replacement cost guide explains what changes the price, and the steps in how to test an alternator help confirm it first.
- Replace damaged battery wires and clean corrosion from connectors
- Replace blown fuses, and find out what blew them
- Test or replace a worn battery when it fails the engine-off reading
- Test the alternator and voltage regulator when running voltage stays low
Repair costs vary by vehicle and shop, and this page does not list fixed price ranges.
The code is generic, so its definition is the same across makes, but the wiring layout and exact voltage targets are not. This page uses the general ranges above. For specific values and connector locations, the vehicle’s own service information is the final reference.
Frequently Asked Questions
Can a bad battery alone cause P0562?
Yes, a worn-out battery is one of the listed causes for P0562. A battery that cannot hold charge can pull the system voltage down. Test it with the engine off first. If it reads low, replace it and retest the charging system to confirm the code stays off.
Does P0562 always mean the alternator is bad?
No. A faulty alternator or voltage regulator is one listed cause, but loose wiring, corroded connectors, blown fuses, high-resistance battery cables and battery drain can trigger the same code. Testing the battery, wiring and running voltage helps separate these before you replace any part.
Will clearing the code fix P0562?
Clearing the code erases the stored record, but it does not repair the cause. If voltage still drops below the trigger while the engine runs, the powertrain control module will set the code again. Fix the underlying fault first, then clear the code and confirm it stays off.
Is 12.6 volts normal with the engine off?
Yes, about 12.6 volts is the normal engine-off reading according to Mechanicbase. Kelley Blue Book gives a figure of at least 12.4 volts. A reading well below that suggests a weak or bad battery, so test or recharge the battery before blaming the charging system.
What does a reading below 12 volts with the engine running mean?
Kelley Blue Book says a running reading below 12 volts likely points to a charging problem. Check the alternator output, the voltage regulator and the battery cable connections first. A healthy system should show about 13.5 to 14.5 volts with the engine running.
Can a basic OBD2 code reader show P0562?
Yes. A basic OBD-II code reader can read P0562 and any other stored codes. Write down every code before clearing anything, because other codes can point to the same charging fault.
Can a loose battery cable cause P0562?
Yes. High resistance in battery cables and loose or corroded wiring are both listed causes. Clean the terminals and tighten the connections, then measure the running voltage again. If the reading rises into the normal range, the connection was the likely problem.
If P0562 appears alongside stalling, or a battery warning light, avoid long drives and have the charging system checked before you travel far. Read the stored codes first, then test voltage with the engine off and running, so the repair targets the actual fault instead of a guess.
