P0961
DTC P0961
Circuit Description
The pressure control (PC) solenoid valve is located in the valve body. The PC solenoid valve controls transmission line pressure based on current flow through its windings. The transmission control module (TCM) determines desired line pressure based on throttle position and other inputs. The TCM then varies the duty cycle on the high side of the PC solenoid valve to control current flow to the solenoid. Current is controlled from about 0.02 amps for maximum line pressure to 1.1 amps for minimum line pressure. The TCM monitors the actual current to the solenoid.
If the TCM detects a commanded current draw that differs from the actual current draw by more than a calibrated value, then DTC P0961 sets. DTC P0961 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0961 Line Pressure Control (PC) Solenoid System Performance
Conditions for Running the DTC
The PC solenoid valve is enabled.
Conditions for Setting the DTC
DTC P0961 sets when the duty cycle is outside the range of 0.5-95 percent for 4 seconds.
Action Taken When the DTC Sets
^ The TCM does not illuminate the malfunction indicator lamp (MIL).
^ 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 Failure Records.
^ The TCM stores DTC P0961 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.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step verifies that the fault is present.
3. This step tests the transmission wiring harness and the PC solenoid valve for correct resistance.
9. This step begins diagnosis of the engine side of the circuit.
Step 1 - Step 7:
Step 8 - Step 16:
