Error Code P0562 is defined as System Voltage Low. It’s a strictly electrical issue.

This error code is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II system, especially those made since 1996 up to present. It’s commonly found in Kia, Hyundai, Jeep, Mercedes, Dodge, Ford and GM vehicles, however. Specifications on the definition, troubleshooting, and repairs, of course, vary from one make and model to another.

Definition

The job of the Charging System is to keep an ideal voltage level (usually around 14.1V to 14.4V DC) when the vehicle is in idle and with lights turned off.

The PCM (powertrain control module, also known as ECM or engine control module) monitors the ignition feed circuit to determine if the charging system is working properly. If the voltage is too low (lower than 10V for more than 60 seconds) or lower than the requested vehicle voltage, then Error Code P0562 will be set.

Common Symptoms

As with other error codes, this code activates the Check Engine light and registers the code to the vehicle’s memory system. Also, since it refers to system voltage being low, then it will illuminate the Battery Light on the dashboard as well. Other common symptoms include:

  • Vehicle unable to shift properly
  • Increase in fuel consumption
  • Dying when coming to a stop
  • Misfire-like symptoms

There are cases, however, that the vehicle may not show any noticeable symptoms.

Possible Causes

There are a lot of factors that could lead to this code, namely:

  • Faulty alternator
  • Faulty alternator wirings or connectors
  • Faulty B+ battery cable from alternator to battery
  • Bad charging system ground(s)
  • Faulty PCM (rare)
  • Faulty PCM wiring/connection to alternator
  • Faulty voltage regulator
  • Faulty battery and/or cables
  • Large parasitic battery drain

How to Check

As with other codes, technicians take note of other codes present in the system, as well as the freeze frame data of the vehicle when the code was set when diagnosing this code.

Then, technicians will try to replicate the code-setting conditions and take the vehicle for a test drive to see if the code comes back.

They make sure the check voltage output from the Alternator B+ terminal and check the voltage drops from Battery power, and ground terminals for the charging system.

Obviously, they also have to pay attention to the scan tool data, especially on the charging system requested voltage vs. the actual vehicle system voltage. In some cases, this code can be quite tricky to detect, so they observe these things while changing the engine load, throttle position, RPM, and the road speed.

How to Fix

In many cases, the vehicle may need a new set of accelerator pedal position sensor. Of course, the combination of faults, including problems in the wiring harness or internal fault in the controller itself, must be properly diagnosed and fixed.

Connectors and wirings must be thoroughly checked; any scrapping, rubbing, bare wires, melted plastics, or burn spots are signs of problems. They must be repaired and/or replaced as needed. Terminals must also be cleaned. Technicians usually use contact cleaner and plastic bristle to brush clean the terminals as needed. Let them dry before applying electrical grease to the terminal contacts.

If after doing the diagnosis and repairs the problem persists, then the fault must be caused by failed PCM. Before replacing the PCM of course, it should be thoroughly diagnosed as well. When replacing PCM, it must be reprogrammed and calibrated for the vehicle to install properly.

The most common cause of this code is low battery voltage, disconnected battery, or charging system malfunction (defective alternator). Thus, these things must be checked first.