DTC P0563 System Voltage High

Object Number: 218506  Size: PAGE-WIDE
Click here for detailed picture of above image.

Circuit Description

The PCM continuously monitors the system voltage. The system voltage information is taken from the PCMs ignition feed circuits. Since voltages below 8.0 volts or above 17.1 volts, could cause improper system operation and/or component damage, the PCM operates in a default mode if a PCM voltage DTC sets. If the system voltage is low the PCM raises the idle speed in order to increase the generator output. If the system voltage is high, the PCM disables most outputs to protect the hardware. A scan tool may not display data if system voltage is outside this range. Because of this, use a DMM in order to monitor system voltage to verify if the fault is currently present.

Conditions for Running the DTC

The engine run time is greater than 10 seconds.

Conditions for Setting the DTC

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Diagnostic Aids

For an intermittent, refer to Symptoms .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for excessive generator output. The voltage should remain below 17.1 volts.







Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?


Go to Step 2

Go to A Powertrain On Board Diagnostic (OBD) System Check



If DTC P1635 and/or P1639 are set, refer to those DTCs for further diagnosis.

  1. Turn OFF all the accessories.
  2. Measure the battery voltage at the battery using the DMM J 39200 .
  3. Operate the engine speed above 2000 RPM.

Is the battery voltage less than the specified value?


Go to Diagnostic Aids

Go to Step 3


Repair the Charging system. Refer to Charging System Check in Engine Electrical. Is the repair completed?


Go to Step 4



  1. Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.
  2. Idle the engine at the normal operating temperature.
  3. Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.

Does the scan tool indicate that this test ran and passed?


Go to Step 5

Go to Step 2


Select the Capture Info option and the Review Info option using the scan tool. Does the scan tool display any DTCs that you have not diagnosed?


Go to the applicable DTC table

System OK