The transmission control module (TCM) calculates last shift status based on data from the automatic transmission input shaft speed and output shaft speed sensors. The TCM measures the amount of time required to complete each shift.
If the TCM detects incorrect shifting, indicating excessive slip or drag within the transmission, then DTC P1719 sets. DTC P1719 is a type A DTC.
This diagnostic procedure supports the following DTC:
DTC P1719 Incorrect Shifting Detected
• | No TFT DTCs P0711, P0712 or P0713. |
• | No OSS DTC P0722. |
• | No engine speed signal DTC P0727. |
• | No engine torque signal DTC P1781. |
• | No multiplex shifting |
• | The ignition voltage is 10.2-15.5 volts. |
• | The transmission temperature is 60°C (140°F) or greater. |
• | The transmission is in a forward range. |
• | Trans. protection mode is OFF. |
The TCM commands a gear shift, and one of the following occurs 5 times:
• | Long |
• | Short |
• | Tie-up |
• | Flare |
• | The TCM requests the powertrain control module (PCM) 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 requests the PCM to limit engine torque to 150 N·m (111 lb ft). |
• | 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 TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Record. |
• | The TCM stores DTC P1719 in TCM history. |
• | The PCM 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 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 ignition is OFF long enough in order to power down the TCM. |
Ask the customer about overloading the vehicle, exceeding the trailer towing limit, or towing in DRIVE (D).
The numbers below refer to the step numbers on the diagnostic table.
This step tests for low fluid level, which may cause slipping, and result in an incorrect gear ratio.
This step tests for low line pressure.
Step | Action | Values | Yes | No | ||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle in Vehicle DTC Information? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||||||||||||||||
2 |
Refer to Fluid Leak Diagnosis . Did you find and correct a condition? | -- | Go to Step 12 | Go to Step 3 | ||||||||||||||||||||
Inspect for correct transmission fluid level. Refer to Transmission Fluid Check . Is the action complete? | -- | Go to Step 4 | -- | |||||||||||||||||||||
4 |
Important:
Does the Last Shift Status of any gear shift indicate Long, Short, Tie-up, or Flare? | -- | Go to Step 5 | Go to Intermittent Conditions in Engine Controls - 3.4L | ||||||||||||||||||||
Test for correct line pressure. Refer to Line Pressure Check . Is the action complete? | -- | Go to Step 6 | -- | |||||||||||||||||||||
6 |
Did you find excessive amounts of sediment? | -- | Go to Step 10 | Go to Step 7 | ||||||||||||||||||||
7 | Inspect the control valve body assembly (39) for the following conditions:
Did you find any of the above conditions? | -- | Go to Step 9 | Go to Step 8 | ||||||||||||||||||||
8 | Has the control valve body been serviced within the past 3 months or 4,828 km (3,000 mi)? | -- | Go to Step 10 | Go to Step 9 | ||||||||||||||||||||
9 | Repair or replace the control valve body assembly. Refer to Control Valve Body Replacement . Is the action complete? | -- | Go to Step 12 | -- | ||||||||||||||||||||
10 | Inspect the following items:
Did you find any problem with the above items? | -- | Go to Step 11 | Go to Step 13 | ||||||||||||||||||||
11 | Repair or replace the transmission. Refer to Transmission Replacement . Is the action complete? | -- | Go to Step 12 | -- | ||||||||||||||||||||
12 |
Refer to Transmission Fluid Replacement . Important: The Clear TAPS function will clear all adapt cells. This may affect transmission performance. The TCM will update the adapt cell values as the vehicle is driven.
Did you complete the above procedures? | -- | Go to Step 14 | -- | ||||||||||||||||||||
13 | Replace the transmission control module (TCM). Refer to Control Module References in Computer/Intergrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 14 | -- | ||||||||||||||||||||
14 | Perform the following procedure in order to verify the repair:
Does the DTC reset? | -- | Go to Step 2 | Go to Step 15 | ||||||||||||||||||||
15 | 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 - Vehicle in Vehicle DTC Information | System OK |