The transmission control module (TCM) continuously monitors the system voltage on the Ignition 1 and the battery circuits. Higher than normal voltage may cause the solenoids inside the transmission to operate improperly or damage solid-state components inside the TCM.
When the TCM detects high voltage, 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 18 volts or greater for 10 seconds.
• | The TCM does not request the engine control module (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 records this information as a Failure Record. |
• | 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 fault no longer exists and the DTC passes. |
• | Observe the driver information center (DIC) messaging that would indicate the electrical system requires service. |
• | 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 | Value(s) | Yes | No | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||||||
2 |
Important:
Did you record a Failure Record for DTC P0562? | -- | Go to DTC P0562 | Go to Step 3 | ||||||||
3 |
Is the charge indicator light ON? | -- | Go to Charging System Test | Go to Step 4 | ||||||||
Is the voltage within the specified range? | 12.5-14.5 V | Go to Step 5 | Go to Charging System Test | |||||||||
Is the difference between the voltage displayed on the scan tool and the voltage measurement in Step 4 greater than the specified value? | 1.0 V | Go to Step 7 | Go to Step 6 | |||||||||
6 | Did P0563 reset? | -- | Go to Step 7 | Go to Testing for Intermittent Conditions and Poor Connections | ||||||||
7 | Replace the TCM. Refer to Control Module References . Is the action complete? | -- | Go to Step 8 | -- | ||||||||
8 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 9 | Go to Step 2 | ||||||||
9 | 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 |