The transmission control module (TCM) samples the system voltage on the ignition 1 circuit every 0.1 seconds. Higher than normal voltage may cause the transmission control solenoids to operate improperly or damage the solid-state components inside the TCM.
If the TCM detects high voltage for a number of samples, DTC P0563 sets. DTC P0563 is a type C DTC.
This diagnostic procedure supports the following DTC:
DTC P0563 System Voltage High
The ignition is ON.
The TCM detects system voltage is 18 volts or greater for 10 seconds.
• | The TCM does not request the ECM to illuminate the malfunction indicator lamp (MIL). |
• | The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records. |
• | The TCM stores DTC P0563 in TCM history. |
• | A scan tool can clear the DTC. |
• | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring. |
• | The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM. |
• | Use the scan tool in order to inspect all other modules for voltage related DTCs. |
• | Running the engine with a battery charger attached may cause DTC P0563 to set. |
- | Inspect the charging circuit for high resistance. |
- | Inspect the vehicle battery for open or sulfated cells. |
The numbers below refer to the step numbers on the diagnostic table.
This step tests the charging system voltage with a minimal load.
This step obtains the ignition voltage measurement reported by the TCM.
Step | Action | Values | Yes | No | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||||
2 |
Important:
Is the battery charge indicator lamp ON? | -- | Go to Step 3 | |||||||||
Is the voltage within the specified range? | 12.5-14.5 V | Go to Step 4 | Go to Charging System Test | |||||||||
Is the difference between the voltage displayed on the scan tool and the voltage measurement in Step 3 greater than the specified value? | 1.0 V | Go to Step 6 | Go to Step 5 | |||||||||
5 | Did DTC P0563 reset? | -- | Go to Step 6 | Go to Testing for Intermittent Conditions and Poor Connections | ||||||||
6 | Replace the TCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 7 | -- | ||||||||
7 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 8 | Go to Step 2 | ||||||||
8 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |