P0562 – System voltage -low

Jason

By Jason (Contact Me)
Last Updated 2016-04-29
The Automotive Copywriter

Trouble CodeFault LocationProbable Cause
P0562 System voltage -low Wiring, poor connection, battery, alternator

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What Does Code P0562 Mean?

A vehicle’s electrical system incorporates a charging system that is responsible for keeping the battery at full capacity as well as providing power for the vehicle’s electrical system while the engine is running. In a 12-volt system, a fully-charged battery should measure at 12.6 volts or higher and while the engine is running, the measurement should be in the range of 13.7 to 14.7 volts.

The alternator is the component that recharges the battery and powers your vehicle’s electrical system. If the alternator doesn’t put out an appropriate voltage, the battery reserve depletes and there is insufficient power to operate your car’s electrical functions. A DTC will set in the powertrain control module (PCM) and potentially other modules indicating the low voltage condition, and depending on the vehicle design, a low voltage warning message or battery light may illuminate.

Trouble code P0562 is a Type C DTC and is set in the PCM after just one instance of failure, though it won’t illuminate the malfunction indicator lamp (MIL) or Check Engine light. In most vehicles, the DTC is set when the voltage reading is less than 11 volts for at least 15 seconds, and in some cases, the DTC will set immediately if the voltage is significantly less than 10 volts.

What are the common causes of code P0562 ?

  • Loose or damaged terminals at the alternator
  • PCM failure
  • Loose or worn alternator drive belt or serpentine belt
  • Corroded, broken, or chafed wiring
  • Insufficient battery charge or bad cell in battery
  • Poor wiring connection
  • Failed alternator
  • Loose positive or negative battery terminal

What are the symptoms of code P0562 ?

  • DTC P0562 will record a trouble code in the PCM
  • The battery light may illuminate
  • Low voltage warning,  battery warning, or a charging system failure warning on the instrument panel
  • Difficulty restarting the engine
  • Flickering or dimming headlights and interior lights
  • Audio system cuts out or turns off
  • Erroneous DTC’s cause MIL to illuminate
  • Improper shifting

How do you troubleshoot code P0562 ?

To trace the problem with DTC P0562,the most helpful tool is a digital volt-ohm meter or DVOM.

1. Visual inspection

A basic visual inspection is the best place to begin troubleshooting. With the engine turned off, inspect under the hood for indications of an alternator failure, loose connections, and a belt with improper tension. Press on the alternator drive belt to ensure there is sufficient tension to turn the pulley. Check for flat spots and signs of glazing or burning that would indicate a seized or failing alternator. Replace a stretched belt or weak tensioner before proceeding with further diagnosis.

Wiggle the battery cable clamps at the battery, ensuring they are well tightened and immovable by hand. Look for corrosion at the battery terminals, cracks or fraying on the battery cables.

2. Charging system test

With the engine running and all the vehicle accessories powered off, measure the battery voltage at the battery terminals with your DVOM. The reading should be anywhere from 12.6 to 15.0 volts. If the reading is below 12.6 volts, the battery is not receiving a charge from the alternator. This condition is typically due to a failed alternator which will be accompanied by hard starting, dim lights, and electrical functions such as the wipers and power windows operating slower or not at all.

If the voltage reading is within the normal range, you may have an intermittent condition or wiring issue causing your concern and setting a DTC for low voltage.

3. Wiring inspection

At the alternator, ensure all connections are properly seated or tight. Check for loose pins, fractures in the wire insulation, and signs of corrosion or water in the connector. Ensure the lock tabs on all alternator connectors are fully engaged to prevent poor connections.

Very carefully, trace the wiring from the alternator to the powertrain control module with the engine running, being mindful of the belt, pulleys and other moving parts. Perform a wiggle test along the length of each wire, monitoring your voltage for changes as you wiggle the wires. If the voltage drops or spikes significantly while performing your wiggle test in a particular area, repair the break and retest.

Check the connection at the PCM. Ensure there isn’t any corrosion or moisture at the corresponding pins, then ensure the connector is fully seated onto the module.

4. Battery test

battery voltage

With the engine off, test the battery with your DVOM at the battery posts. Battery voltage should be 12.0 to 12.6v and should maintain the voltage without dropping. Significant reduction in voltage indicates either a battery failure or a large parasitic draw, both of which can cause DTC P0562 to set.

alternator test

You can also test the for proper battery voltage to the alternator. Measure the voltage between the positive terminal on the alternator and ground. Voltage should match that of the battery voltage at the battery. If it does not, the positive alternator circuit needs to be repaired.

Codes Related to P0562

P0563 – System voltage high

BAT Team Discussions for P0562

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