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For 1990-2009 cars only

DTC P0563 w/2.0L (L34 GMDAT)

Circuit Description

The engine control module (ECM) uses the ignition 1 voltage circuit to monitor system voltage. Voltage that is out of range will cause damage to components and incorrect input readings. If the ECM detects an excessively high system voltage, DTC P0563 will set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0563 System Voltage High

Conditions for Running the DTC

    • The ignition is ON with the engine OFF.
    • DTC P0563 runs continuously once the above condition is met.

Conditions for Setting the DTC

The ECM detects a system voltage above 16 volts for more than 5 minutes.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Step

Action

Value

Yes

No

Schematic References: Engine Controls Schematics in Engine Controls - 2.0L (L34), or Engine Controls Schematics in Engine Controls - 2.5L (LBK)

Connector End View References: Engine Controls Connector End Views in Engine Controls - 2.0L (L34), Engine Controls Connector End Views in Engine Controls - 2.5L (LBK), Engine Control Module Connector End Views in Engine Controls - 2.0L (L34) or Engine Control Module Connector End Views in Engine Controls - 2.5L (LBK)

1

Did you perform the Diagnostic System Check - Engine Electrical?

--

Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2

  1. Start the engine.
  2. Raise the engine speed above 1,500 RPM.
  3. With a scan tool, observe the Ignition 1 voltage parameter in the Engine Control Module (ECM) data list.

Is the voltage less than the specified value?

16.0 V

Go to Step 3

Go to Step 4

3

  1. Observe the Freeze Frame/Failure Records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 4

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

4

  1. Measure the voltage at the battery with a DMM.
  2. Raise the engine speed above 1,500 RPM.
  3. Compare the voltage at the battery to the Ignition 1 parameter in the ECM data list.

Is the battery voltage and Ignition 1 parameter readings different by more than the specified value?

0.5 V

Go to Step 5

Go to Charging System Test

5

Replace the ECM. Refer the appropriate procedure:

    •  Engine Control Module Replacement in Engine Controls - 2.0L (L34)
    •  Engine Control Module Replacement in Engine Controls - 2.5L (LBK)

Did you complete the replacement?

--

Go to Step 6

--

6

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 7

7

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 2.0L (L34) Diagnostic Trouble Code (DTC) List in Engine Controls - 2.5L (LBK)

System OK

DTC P0563 w/2.5L (LBK)

Circuit Description

The engine control module (ECM) monitors the voltage supplied on the feedback circuit of the engine controls ignition or ENG MAIN relay. Voltage that is out of range will cause incorrect input readings from the engine components connected to the relay. If the ECM detects voltage present on the feedback circuit of the engine controls ignition or ENG MAIN relay when the ignition is turned OFF, DTC P0563 will set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0563 Engine Controls Ignition Relay Feedback Circuit High Voltage

Conditions for Running the DTC

    • The ignition is cycled from the ON position to the OFF position.
    • DTC P0563 runs continuously once the above condition is met.

Conditions for Setting the DTC

The ECM detects voltage more than 7.9 volts on the feedback circuit of the engine controls ignition or ENG MAIN relay when the ignition is turned OFF for more than 1 second.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

    • For an intermittent condition, refer to Intermittent Conditions .
    • The following table illustrates the ENG Main relay terminal location in the underhood fuse block:

ENG Main Relay Terminal Identification

Feeback

Control

B+ - Coil

B+ - Switch

Front of Vehicle

Step

Action

Values

Yes

No

Schematic References: Engine Controls Schematics in Engine Controls - 2.5L (LBK)

Connector End View References: Engine Control Module Connector End Views or Engine Controls Connector End Views in Engine Controls - 2.5L (LBK)

1

Did you perform the Diagnostic System Check - Engine Electrical?

--

Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2

Are DTCs P1610 or P1611 also set?

--

Go to Diagnostic Trouble Code (DTC) Listin Engine Controls - 2.5L (LBK)

Go to Step 3

3

  1. Turn ON the ignition, with the engine OFF.
  2. Clear the DTC with a scan tool.
  3. Turn OFF the ignition for 30 seconds.
  4. Turn ON the ignition, with the engine OFF.
  5. Observe the DTC information with a scan tool.

Does DTC P0563 set?

--

Go to Step 5

Go to Step 4

4

  1. Observe the Freeze Frame/Failure Records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 5

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

5

  1. Turn OFF the ignition.
  2. Disconnect the ENG MAIN relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the ENG MAIN relay switched output terminal at the fuseblock for the feedback circuit of the relay with a test lamp connected to a good ground.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 7

6

Test all circuits that have voltage supplied by the ENG MAIN relay including the feedback circuit of the relay for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 8

7

Test for shorted terminals or poor connection at ENG MAIN relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairsin Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

8

Test for shorted terminals or poor connection at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairsin Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Replace the ENG MAIN relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

--

Go to Step 11

--

10

Replace the ECM. Refer to Engine Control Module Replacement in Engine Controls - 2.5L (LBK).

Did you complete the replacement?

--

Go to Step 11

--

11

  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 12

12

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) Listin Engine Controls - 2.5L (LBK)

System OK