OBD-II Code P0560 — What It Means & How to Fix It

What Does This Error Mean?

P0560 means the engine control module detected an abnormal system voltage. The ECM needs a stable voltage supply — typically between 10 and 16 volts — to operate correctly. When voltage falls outside that range, P0560 is triggered. This code often points to a weak battery, a failing alternator, or a bad ground connection. Other systems like transmission shifting and fuel trims may also be affected until this is fixed.

Affected Models

All vehicles 1996+
Common in GM cars and trucks
Common in Ford vehicles
Common in Chrysler, Dodge, and Jeep vehicles
Common in any vehicle with aging battery or alternator

Common Causes

Weak or failing battery no longer holding a full charge
Failing alternator not maintaining proper charging voltage
Loose, corroded, or damaged battery cables or terminals
Poor engine or chassis ground connection causing voltage drops
Parasitic electrical drain pulling down battery voltage

How to Fix It

Test the battery first. Most auto parts stores offer free battery testing. A healthy battery should test at 12.6 volts or higher when fully charged with the engine off.

A battery below 12.4 volts at rest is weak and may need replacement, especially if it is more than 3 to 5 years old.
Check battery terminals and cable ends for corrosion — a white, blue, or greenish buildup. Clean them with a wire brush and baking soda solution if corroded.

Even a small amount of corrosion can cause significant voltage drop and trigger P0560.
Test the alternator output voltage with a multimeter. With the engine running at around 1500 RPM, the battery should read 13.5 to 14.8 volts. Below that indicates a failing alternator.

Auto parts stores also test alternators for free in many cases.
Inspect engine-to-chassis ground straps and battery negative cable connections at both ends. A loose or corroded ground causes voltage irregularities throughout the electrical system.

There is often a ground strap from the engine block to the firewall and another from the battery to the chassis.
Replace the battery or alternator based on test results. Clear the code and monitor system voltage with a scan tool on a test drive to confirm the reading stays in the 13.5 to 14.8 volt range.

If the voltage is erratic while driving, have the alternator wiring and voltage regulator inspected.

When to Call a Professional

Battery and alternator testing can be done free at most auto parts stores. A new battery typically costs $100 to $200 installed. A remanufactured alternator costs $150 to $300 for the part. Alternator installation labor is $100 to $250 depending on accessibility. Ground connection repairs are usually inexpensive if you can locate the bad ground.

Frequently Asked Questions

Can a bad battery cause P0560?

Yes — this is one of the most common causes. A weak battery can cause voltage to dip below the ECM's acceptable range, especially during starting. Replacing a failing battery often clears this code without any other repair needed.

Will P0560 go away on its own?

It will only go away once the root cause is fixed. If a loose terminal was the cause, tightening it may clear the code after a few drive cycles. But a failing battery or alternator will not fix itself.

Can P0560 damage my car's computer?

Prolonged low or high voltage can stress the ECM and other control modules. Most vehicles have some voltage protection built in. However, it is best to fix the root cause promptly to avoid risks to expensive electronics.