Circuit Description
The engine control module (ECM) checks the system voltage to make sure that the voltage stays within the proper range. Damage to components, and incorrect 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 an excessively low system voltage, DTC P0562 will set.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0562 System Voltage Low
Conditions for Running the DTC
| • | Engine speed above 1,500 RPM. |
| • | System voltage between 9.5-18 volts. |
Conditions for Setting the DTC
The ECM detects a system voltage below 10 volts for 5 seconds.
Action Taken When the DTC Sets
| • | The ECM will command a message to be displayed. |
| • | The ECM will not illuminate the malfunction indicator lamp (MIL). |
| • | The ECM will store conditions which were present when the DTC set as Fail 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 | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics in Engine Controls - 6.0L (LS2) Connector End View Reference: Engine Control Module Connector End Views in Engine Controls - 6.0L (LS2) or Power and Grounding Connector End Views in Wiring Systems | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the scan tool indicate that the Ignition 1 Signal parameter is greater than the specified range? | 10.5 V | Go to Step 6 | Go to Step 3 |
3 | Using a scan tool compare the Battery Voltage Signal parameter in the body control module (BCM) data list with the Ignition 1 Signal parameter in the ECM data list. Is the Battery Voltage and Ignition 1 Signal parameter readings different by more than the value specified? | 0.5 V | 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 in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 5 |
5 | Inspect for poor connections at the harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 6 |
6 | Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 7 | -- |
7 |
Does the scan tool indicate that DTC P0562 failed this ignition? | -- | Go to Step 2 | System OK |
