5L40-E / 5L50-E Automatic Transmission
DTC P0826
Circuit Description
The TAP Shift system allows the driver to manually shift gears by using the TAP Shift switches located on the automatic transmission shifter. Pushing the Up switch will command an upshift and pushing the Down switch will command a downshift. The TAP Shift system is activated when the gear selector is in the manual, M, position and is deactivated in all other positions.
If the transmission control module (TCM) detects an invalid voltage on the Up/Down Switch Circuit, DTC P0826 sets. DTC P0826 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0826 Up and Down Shift Switch Circuit
Conditions for Running the DTC
The engine run time is greater than 5 seconds.
Conditions for Setting the DTC
The TCM detects an invalid voltage on the TAP Up/Down Signal Circuit for 300 seconds.
Action Taken When the DTC Sets
^ The TCM does not request the ECM to illuminate the malfunction indicator lamp (MIL).
^ The TCM disables TAP Shift operation.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
^ The TCM stores DTC P0826 in TCM history.
Conditions for Clearing the DTC
^ 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.
