This diagnostic procedure supports the following DTC:
DTC P0563 System Voltage High
| • | The system voltage is too high. | 
| • | The transmission control module (TCM) detects that the voltage is greater than 18 volts for 0.5 second continuously. | 
| • | The engine revolution is 600 RPM or greater. | 
The TCM will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects failures on 2 consecutive ignition cycles.
| • | The TCM turns OFF the MIL when no further failures are detected on the next ignition cycles. | 
| • | The scan tool can clear the DTC from the TCM history. | 
| • | The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault. | 
| • | The TCM wiring harness and connectors | 
| • | The battery | 
| • | The TCM | 
Step  | Action  | Values  | Yes  | No  | 
|---|---|---|---|---|
1  | Did you perform the Diagnostic System Check - Automatic Transmission?  | --  | Go to Step 2  | |
2  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 5  | Go to Step 3  | 
3  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 5  | Go to Step 4  | 
4  | Replace the battery. Did you complete the replacement?  | --  | System OK  | --  | 
5  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 7  | Go to Step 6  | 
6  | 
 Did you complete the action?  | --  | System OK  | --  | 
7  | Test the EF7, F6 fuse for an open. Was a condition found?  | --  | Go to Step 8  | Go to Step 9  | 
8  | 
 Did you complete the replacement?  | --  | System OK  | --  | 
9  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 11  | Go to Step 10  | 
10  | Repair the fuse voltage supply lines for open. Did you complete the repair?  | --  | System OK  | --  | 
11  | 
 Does the resistance measure the specified value?  | 0 Ω  | Go to Step 13  | Go to Step 12  | 
12  | Repair the circuit between EF7 and terminal A24 for a short to ground and an open. Did you complete the repair?  | --  | System OK  | --  | 
13  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 14  | Go to Step 15  | 
14  | Repair the circuit from EF7 to terminal A24 of the TCM for a short to battery. Did you complete the repair?  | --  | System OK  | --  | 
15  | 
 Does the resistance measure the specified value?  | 0 Ω  | Go to Step 17  | Go to Step 16  | 
16  | Repair the circuit between F6 and terminal A6 for a short to ground and an open. Did you complete the repair?  | --  | System OK  | --  | 
17  | 
 Is the voltage within the specified range?  | 9-16 V  | Go to Step 18  | Go to Step 19  | 
18  | Repair the circuit between F6 and terminal A6 for a short to battery. Did you complete the repair?  | --  | System OK  | --  | 
19  | 
 Was a condition found?  | --  | Go to Step 20  | --  | 
20  | Replace the TCM. Refer to Transmission Control Module Replacement . Did you complete the replacement?  | --  | Go to Step 21  | --  | 
21  | 
 Has the last test failed or is the current DTC displayed?  | --  | Go to Step 2  | System OK  |