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P1835

DTC P1835









Circuit Description with 4L30-E Automatic Transmission
The Engine Control Module (ECM) transmits downshift requests to the Transmission Control Module (TCM) when the accelerator pedal position exceeds 89 percent The ECM sends the downshift request to the TCM on a communication network called the Controller Area Network (CAN). A fault in the CAN will not cause DTC P1835 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P1835.
If the TCM detects a throttle angle lower than 89 percent and the ECM is requesting a downshift, then DTC P1835 sets. DTC P1835 is a type C DTC.

Conditions for Running the DTC
^ The ignition is ON.
^ No Throttle Position Signal DTC P1890.
^ Throttle is less than 89 percent.

Condition for Setting the DTC
ECM is sending a downshift request to the TCM.

Action Taken When the DTC Sets
^ The TCM does not request the ECM to illuminate the MIL.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM records this information as Failure Records.
^ The TCM stores DTC P1835 in TCM history.
^ The TCM will enable downshifts when the throttle reaches its limit.

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 mode actions when the fault no longer exists.