The powertrain control module (PCM) continuously monitors that the system voltage stays within the proper range. If the PCM detects an excessively high system voltage, DTC P0563 will set. A high voltage condition may cause a stalling condition or other driveability concerns.
| • | The engine run time is more than 20 seconds. | 
| • | Engine running above 1200 RPM. | 
| • | Vehicle speed above 8 km/h (5 mph). | 
| • | The PCM senses the system voltage is above 19 volts. | 
| • | All of the conditions are present for 5 seconds. | 
| • | The PCM stores DTC P0563 in the PCM memory when the diagnostic runs and fails. | 
| • | The PCM will record the operating conditions at the time the diagnostic fails. The PCM stores this information in Failure Records. | 
| • | The PCM disables most outputs. | 
| • | The transmission defaults to a predetermined gear. | 
| • | The torque converter clutch (TCC) operation is inhibited. | 
| • | The instrument panel cluster (IPC) displays a message. | 
| • | The malfunction indicator lamp (MIL) will not illuminate. | 
| • | The Conditions for Setting the DTC are no longer present. | 
| • | A history DTC will clear after 40 malfunction free ignition cycles. | 
| • | The Powertrain Control Module (PCM) receives the clear code command from the scan tool. | 
| Step | Action | Value(s) | Yes | No | 
|---|---|---|---|---|
| Schematic Reference: Starting and Charging Schematics Connector End View Reference: Engine Electrical Connector End Views | ||||
| 1 | Did you perform the Engine Electrical Diagnostic System Check? | -- | Go to Step 2 | |
| 
 Is the battery voltage less than the specified value? | 19 V | Go to Step 4 | Go to Step 3 | |
| 3 | Replace the generator. Refer to Generator Replacement . Is the action complete? | -- | -- | |
| 4 | Important: The replacement PCM must be programmed. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L, 6.0L or to Powertrain Control Module Replacement in Engine Controls - 8.1L. Is the action complete? | -- | Go to Step 5 | -- | 
| 5 | 
 Does the DTC reset? | -- | Go to Step 2 | System OK |