Circuit Description
The TCC lock up pressure control (PC) solenoid valve regulates solenoid modulator fluid passing through the solenoid into lock up control pressure. The TCM uses a pulse width modulated signal in order to control the signal pressure. The TCM compares various inputs in order to determine the appropriate pressure for a given load. The TCM varies the current to the TCC lock up PC solenoid valve from 0.1 amps, for maximum line pressure to 1.1 amps, for minimum line pressure. An internal current monitor within the TCM provides feedback in order to determine actual TCC lock up PC solenoid valve current draw.
If the TCM detects a continuous short to voltage in the TCC lock up PC solenoid valve circuit, then DTC P0967 sets. DTC P0967 is a type A DTC.
Conditions for Running the DTC
The ignition voltage is 8-18 volts.
Conditions for Setting the DTC
The TCC lock up PC solenoid valve feedback circuit indicates a continuous short to voltage for 2 seconds or greater.
Action Taken When the DTC Sets
| • | The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL). |
| • | The TCM turns the Trans. Protection Mode ON. When the Trans. Protection Mode is ON, the following conditions occur: |
| - | The transmission will operate in 5th gear when the transmission is shifted into D or I range and 2nd gear when shifted into L range. |
| - | The line pressure is at maximum. |
| - | The torque converter clutch (TCC) is disabled. |
| - | The TCM freezes the 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 P0967 in TCM history. |
Conditions for Clearing the MIL/DTC
| • | The ECM turns off the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request. |
| • | A scan tool can clear the MIL/DTC. |
| • | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an 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. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verifies the ability of the TCM to command the TCC lock up PC solenoid valve.
-
This step verifies that the automatic transmission wiring harness and the TCC lock up PC solenoid valve have correct resistance.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | Go to Diagnostic System Check - Engine Controls in Engine Controls - 3.0L (L81) | ||||
Important:
Does the TCC PC Sol. Actual Current reading vary from the TCC PC Sol. Ref. Current reading by more than the specified amount? | 0.10 amps | Go to Step 3 | Go to Intermittent Conditions in Engine Controls - 3.0L (L81) | |||||
Is the resistance less than the specified value? | 3.8 ohms | Go to Step 4 | Go to Step 5 | |||||
4 | Test the high control circuit (CKT 5511) of the TCC lock up PC solenoid valve and the low control circuit (CKT 5509) of the TCC lock up PC solenoid valve for being shorted together between the AT inline 14-way connector and the TCC lock up PC solenoid valve. Refer to Testing for Continuity in Wiring Systems. Did you find the condition? | -- | Go to Step 8 | Go to Step 9 | ||||
5 | Measure the resistance between terminal 3 and all other terminals, except terminal 10, of the transmission side of the AT inline 14-way connector. Refer to Testing for Continuity in Wiring Systems. Is the resistance between terminal 3 and any other terminal, except terminal 10, less than the specified value? | 100 ohms | Go to Step 8 | Go to Step 6 | ||||
6 | Test the high control circuit (CKT 5511) and the low control circuit (CKT 5509) of the TCC lock up PC solenoid valve for a short to voltage or a short together between the AT inline 14-way connector and the TCM. Refer to Circuit Testing in Wiring Systems. Did you find a condition? | -- | Go to Step 7 | Go to Step 10 | ||||
7 | Repair or replace the wiring harness. Refer to Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 11 | -- | ||||
8 | Repair or replace the internal automatic transmission wiring harness assembly (33). Refer to Wiring Harness Removal and Wiring Repairs in Wiring Systems. Did you complete the replacement? | -- | Go to Step 11 | -- | ||||
9 | Replace the control valve body assembly (39). Refer to Control Valve Body Replacement . Is the replacement complete? | -- | Go to Step 11 | -- | ||||
10 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the replacement complete? | -- | Go to Step 11 | -- | ||||
11 | Perform the following procedure in order to verify the repair:
Does the DTC reset? | -- | Go to Step 2 | Go to Step 12 | ||||
12 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 3.0L (L81) | System OK |
