5L40-E/5L50-E - Automatic Transmission
DTC P1831
Circuit Description
The transmission control module (TCM) provides voltage to the pressure control solenoid, the shift solenoids, and the TCC PWM solenoid through two separate solid-state devices called High Side Drivers, called HSD1 and HSD2. HSD1 provides electrical power to the pressure control solenoid. HSD2 provides power to the shift solenoids. A normal function of the TCM is to run tests on each driver to ensure that it is functioning properly.
When the TCM detects a short to ground on HSD1, then DTC P1831 sets. DTC P1831 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P1831 Pressure Control (PC)/Shift Lock Solenoid Control Circuit Low Voltage
Conditions for Running the DTC
The engine run time is greater than 5 seconds.
Conditions for Setting the DTC
The TCM detects a short to ground on the HSD1 circuit when the HSD1 is commanded ON.
Action Taken When the DTC Sets
* The TCM does not request the ECM to illuminate the malfunction indicator lamp (MIL).
* SERVICE VEHICLE SOON displays on the driver information center (DIC).
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.
* 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 P1831 in TCM history.
Conditions for Clearing the DTC/DIC
* The TCM clears the DIC when the condition no longer exists.
* 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 is OFF long enough in order to power down the TCM.
