For 1990-2009 cars

### Circuit Description

The engine control module (ECM) monitors the system voltage to ensure that the voltage stays within the proper range. Damage to components and incorrect data input can occur when the voltage is out of range. The ECM monitors the system voltage over an extended length of time. If the ECM detects a system voltage outside an expected range for the calibrated length of time, DTC P0560 will set.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0560 System Voltage

### Conditions for Running the DTC

The engine run time is more than 2 seconds.

### Conditions for Setting the DTC

The ECM detects a system voltage below 2.54 volts for 4 seconds.

### Action Taken When the DTC Sets

• | The ECM will not illuminate the malfunction indicator lamp (MIL).

• | The ECM will command the charge indicator to be illuminated on the instrument panel cluster (IPC).

• | The ECM will store conditions which were present when the DTC set as Failure Records data only.

### Conditions for Clearing the DTC

• | The ECM will command the message OFF after one trip in which the diagnostic test has been run and passed.

• | The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

• | The DTC can be cleared by using the scan tool Clear DTC Information function.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Install a scan tool.
2. Start the engine.
3. With a scan tool, observe the Ignition 1 Signal parameter in the engine control module (ECM) data list .

Does the scan tool indicate that the Ignition 1 Signal parameter is within the specified range?

11-15.5V

Go to Step 7

Go to Step 3

3 | Measure the voltage at the battery and compare it with the Ignition 1 Signal parameter. Are the battery voltage and Ignition 1 Signal readings different by more than the value specified? | 0.8V | Go to Step 4 | Go to Charging System Test
4 | Test the battery positive voltage circuit of the ECM for a high resistance. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 5
5 | Test the ground circuit of the ECM for a high resistance. Refer to Circuit Testing and Wiring Repairs. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 6
6 | Inspect for poor connections at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs. Did you find and correct the condition? | -- | Go to Step 8 | Go to Step 7
7 | Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 8 | --
8 |

1. Review and record the scan tool Failure Records data.
2. Clear the DTCs with the scan tool.
3. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
4. Using the scan tool, observe the Specific DTC Information for DTC P0560 until the test runs.

Does the scan tool indicate that DTC P0560 failed this ignition cycle?

-

Go to Step 2

System OK