DTC P0961 V6
DTC Description
This diagnostic procedure supports DTC P0961 Line Pressure Control (PC) Solenoid System Performance.
Circuit Description
The pressure control (PC) solenoid valve is an electronic device that regulates transmission line pressure based on the current flow through its coil winding. The magnetic field produced by the coil moves the solenoid's internal valve, which varies pressure regulator valve. The transmission control module (TCM) controls the PC solenoid valve by applying a varying amount of current of current the solenoid. The applied current can vary from 1.0-1.1 A. Low current 0.1 A, indicates high line pressure. High current, 1.1 A, indicates low line pressure. The duty cycle of the PC solenoid valve is expressed as a percentage of energized on time. Zero percent indicates zero on time, non-energized, or no current flow. Approximately 60 percent at idle indicates maximum on time, energized, or high current flow. The TCM determines the appropriate line pressure for a given load by comparing the throttle position, the engine speed and other inputs.
When the TCM detects a continuous open or short to ground in PC solenoid valve circuit, then DTC P0961 sets.
DTC P0961 is type C DTC.
Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View , Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid diagnosis.
Conditions for Running the DTC
| • | The system voltage is 8-18 V. |
| • | The engine is running. |
Conditions for Running the DTC
The PC solenoid valve duty cycle reaches its high limit, approximately 95 percent, or low limit, approximately 2 percent.
Action Taken When the DTC Sets
| • | The TCM does not request the engine control module (ECM) to illuminate the check powertrain icon. |
| • | The TCM records the operating conditions when the conditions for setting the DTC are met. The TCM records this information as a Failure Record. |
| • | The TCM freezes transmission adaptive functions. |
| • | The TCM commands maximum line pressure. |
| • | The TCM stores DTC P0961 in TCM history. |
Condition for Clearing 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. |
| • | Tech 2 can clear the DTC. |
Diagnostic Aids
DTC P0961 may set under low voltage conditions caused by high electrical system demands.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 Check the ability of the TCM to control the solenoid.
3 Check the resistance of the control valve body wiring harness and the PC solenoid.
5 Check the serviceability of the PC solenoid circuits contained in the control valve body wiring harness.
6-8 Checks the serviceability the power and signal circuits between the TCM and the transmission.
Step | Action | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|
1 | Has the Diagnostic System Check been performed? | Got to Step 2 | |||||||
2 |
Important: Before clearing the DTC use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure Record records from the TCM. Transmission/Automatic Transmission/ Diagnostic Trouble Codes/ Freeze Frame. Diagnostic Trouble Codes/ Clear Engine and Transmission DTCs. Miscellaneous Test / Pressure Control Solenoid. Does the Tech 2 display the PC as On and Off when commanded by Tech 2? | Check for intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | ||||||
3 |
Does the multimeter display 3-7Ω? | Go to Step 4 | Go to step 5 | ||||||
4 | Using the multimeter set the measure resistance, probe between connector X121-X1 pin C and the transmission case. | Go to Step 6 | Go to Step 5 | ||||||
5 | Test the circuits 1228 and 1229 between connectors X121-X1 an the solenoids for the following:
Did you find any of the conditions tested? | Replace the control valve body wiring harness, refer to Control Valve Body and Wiring Harness Removal Go to Step 11 | Replace the PC solenoid value, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness Go to Step 11 | ||||||
6 |
Does the multimeter display 3-7Ω? | Go to Step 7 | Go to Step 8 | ||||||
7 | Using a multimeter set a measure resistance, probe between connector A112-X1 pin 40 and a known ground. Does the multimeter display greater than 250 kΩ? | Got to Step 9 | Go to Step 8 | ||||||
8 | Test circuits 1228 and 1229 between connectors X121-X1 and A112-X1 for the following:
Did you find any of the conditions tested? | Repair or replace the affected circuit Go to Step 11 | -- | ||||||
9 | Test circuits 1228 and 1229 for short to voltage between connectors X121-X1 and the solenoid. Did you find and correct the condition? | Go to Step 11 | Go to Step 10 | ||||||
10 | Replace the TCM, refer to Transmission Control Module Replacement. Did you complete the replacement? | Go to Step 11 | -- | ||||||
11 | Perform the following procedure in order to verify the repair:
Diagnostic Trouble Codes/ Clear Engine and Transmission DTCs. Data Display/ Pressure Control Solenoids Data. Diagnostic Trouble Codes/ Read DTC Information. Has DTC P0961 set? | Go to Step 2 | Go to Step 20 | ||||||
12 | On Tech 2 select: Trouble Codes/ Read DTC Information. Does Tech 2 display any DTCs you have not diagnosed? | Refer to Scan Tool Data List | System OK | ||||||
When all diagnosis and repair are completed, check the system for correct operation. | |||||||||
