GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2000 🢒 Sonoma Pickup - 2WD 🢒 DTC 🢒 DTC P0563 System Voltage High

Object Number: 211077 Size: SF
Engine Controls Components
MIL, Generator, and Fuel Composition Sensor
OBD II Symbol Description Notice
Powertrain Control Module Connector End Views
Handling ESD Sensitive Parts Notice

Circuit Description

The powertrain control module (PCM) monitors the system voltage on the ignition feed terminals to the PCM. A system voltage DTC sets whenever the voltage is above a specified calibrated value.

Conditions For Setting The DTC

The system voltage is more than 17.0 volts.

Action Taken When the DTC Sets
    • The PCM records the operating conditions at the time the diagnostic fails. The Failure Records buffers stores this information.
    • A history DTC is stored.

Conditions for Clearing the DTC
    • A history DTC clears after 40 consecutive warm up cycles without a fault.
    • The scan tool can clear the DTC.

Diagnostic Aids
    • Charging the battery with a battery charger and starting the engine can cause a DTC to set.
    • If the DTC sets when you operate an accessory, check for a poor connection or an excessive current draw.
    • Additional DTCs can set as the result of the PCM disabling the outputs.

Test Description

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

  1. The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the Freeze Frame and Failure Records data on the scan tool if applicable. This creates an electronic copy of the data captured when this DTC sets. The scan tool stores this data for later reference.

    2.

  2. Reprogram the replacement PCM and perform the Crankshaft Position System Variation Learn Procedure. Refer to the latest Techline procedures for PCM reprogramming.

    3.

  3. If no malfunctions are present at this point and no additional DTCs were set. Refer to Diagnostic Aids for additional checks and information.

Step

Action

Values

Yes

No

1

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

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2
  1. Turn OFF all of the accessories.
  2. Install a scan tool.
  3. Start the engine.
  4. Raise the engine RPM to the specified value.

Is the ignition voltage more than the specified value?

1400 RPM

17 V

Go to Step 3

Go to Step 5

3

Measure the battery voltage at the battery while running the engine at the specified value using a DMM.

Is the battery voltage less than the specified value?

2000 RPM

17 V

Go to Step 4

Go to Charging System Test in Engine Electrical

4

  1. Turn OFF the ignition .

    2. Important: The replacement PCM must be programmed.

  2. Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

--

Go to Step 5

--

5
  1. Use the scan tool in order to clear the DTCs.
  2. Start the engine.
  3. Idle the engine at the normal operating temperature.
  4. Operate the vehicle within the Conditions for Setting this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic has Ran and Passed?

--

Go to Step 6

Go to Step 2

6

Check to see if any DTCs are set.

Does the scan tool display any DTCs that you have not diagnosed?

--

Go to applicable DTC table

System OK