Technical Description of OBD-II Trouble Code
The vehicle’s system voltage is low.
What does this mean?
This generic diagnostic trouble code is applicable to all vehicles manufactured from 1996 onwards, including Kia, Hyundai, Jeep, Mercedes, Dodge, Ford, and GM vehicles.
On these vehicles, the powertrain control module (PCM) has some control over the charging system. It can regulate the voltage regulator inside the alternator by controlling a power or ground circuit.
The PCM monitors the ignition feed circuit to determine if the charging system is functioning properly. If the voltage is too low, a fault code will be stored. This issue is purely electrical in nature.
The troubleshooting steps may vary depending on the manufacturer, type of charging system control, and wire colors.
Symptoms
The symptoms of an engine code P0562 may include:
Causes
Possible causes for this code to be set are:
Diagnostic and Repair Procedures
A good starting point is to check for technical service bulletins (TSB) specific to your vehicle. There may be a known issue with a known fix provided by the manufacturer, which can save you time and money during diagnosis.
The most common cause for this code is low battery voltage, a disconnected battery, or a malfunctioning charging system (faulty alternator). It is also important to check the alternator belt, which is often overlooked.
First, check the charging system. Start the vehicle and turn on the headlights and blower fan to high speed to load the electrical system. Use a digital volt ohm meter (DVOM) to check the voltage at the battery. It should be between 13.2 volts and 14.7 volts. If the voltage is significantly below 12 volts or above 15.5 volts, diagnose the charging system with a focus on the alternator. If unsure, have the battery, starting system, and charging system tested at a local parts store or auto repair shop. Many places offer this service for a small charge or for free, and they will usually provide a printout of the test results.
If the voltage was correct and you have a scan tool, clear the diagnostic trouble codes from memory and see if this code returns. If it does not, it is likely an intermittent issue or a history/memory code, and no further diagnosis is necessary.
If the P0562 code does return, locate the PCM on your specific vehicle and visually inspect the connectors and wiring. Look for any signs of scraping, rubbing, bare wires, burn spots, or melted plastic. Separate the connectors and carefully inspect the terminals inside. Check for any signs of burning or corrosion, and clean the terminals if necessary using electrical contact cleaner and a plastic bristle brush. Allow them to dry and apply electrical grease to the contact points.
Next, clear the diagnostic trouble codes from memory using the scan tool and see if this code returns. If it does not, then the issue was likely related to the connections.
If the P0562 code does return, the voltages to the PCM need to be checked. Start by disconnecting the negative battery cable and the harness going to the PCM. Reconnect the battery cable and turn the ignition switch on. Use a DVOM to test the PCM ignition feed circuit (red lead to the PCM ignition feed circuit, black lead to a good ground). If the voltage on this circuit is less than the battery voltage, repair the wiring between the PCM and the ignition switch.
If that is okay, check for a good ground at the PCM. Connect a test light to the positive terminal of a 12V battery and touch the other end of the test light to the ground circuit going to the PCM ignition feed circuit ground. If the test light does not illuminate, there is a problem with the circuit. If it does illuminate, wiggle the wiring harness going to the PCM to see if the test light flickers, indicating an intermittent connection.
If all previous tests have passed and you continue to receive a P0562 code, it is likely a failed PCM. If unsure, seek assistance from a trained automotive diagnostician. PCMs must be programmed or calibrated to the vehicle in order to be installed correctly.
