P1845

DTC P1845

Steps 1-6:

Steps 7-15:

Steps 16-23:

Circuit Description
The 2-3 shift solenoid (SS) valve controls the transmission fluid pressure acting on the 1-2 and 2-3 shift valves to position the valves for the appropriate gear. The 2-3 SS valve is a normally open exhaust valve located on the lower control valve body. Ignition voltage is supplied to the solenoid. The output driver module (ODD), within the PCM, commands the solenoid ON or OFF by providing a ground path. When the 2-3 SS valve is commanded ON, the PCM senses low voltage. When the 2-3 SS valve is commanded OFF, the PCM senses high voltage.
If the PCM detects a continuous open or short to ground in the 2-3 SS valve circuit, then DTC P1845 sets. DTC P1845 is a type A DTC.

Conditions for Running the DTC
The engine run time is greater than 5 seconds.

Conditions for Setting the DTC
The 2-3 SS valve feedback circuit indicates a continuous open or short to ground for 4.3 seconds.

Action Taken When the DTC Sets
^ The PCM illuminates the malfunction indicator lamp (MIL).
^ The PCM commands an immediate landing to 2nd gear.
^ The PCM commands maximum line pressure.
^ The PCM inhibits TCC engagement.
^ The PCM freezes transmission adaptive functions.
^ The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
^ The PCM stores DTC P1845 in PCM history.

Conditions for Clearing the MIL/DTC
^ The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
^ A scan tool can clear the MIL/DTC.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
^ The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
8. This step tests the electrical operation of the solenoid.
9. This step verifies the PCMs ability to command the solenoid.
17. This step verifies that the circuit has the correct resistance.