For 1990-2009 cars

### Circuit Description

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.

### DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1719 Incorrect Shifting Detected

### Conditions for Running the DTC

• | No transmission fluid temperature (TFT) DTCs P0711, P0712 or P0713.

• | No output speed sensor (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.

### Conditions for Setting the DTC

The TCM commands a gear shift, and one of the following occurs 5 times:

• | Long

• | Short

• | Tie-up

• | Flare

### Action Taken When the DTC Sets

• | The TCM requests the powertrain control module (PCM) to illuminate the malfunction indicator lamp (MIL).

• | The TCM turns the Trans. Protection Mode ON.

• | The transmission will operate in 5th gear when the transmission is shifted into D 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 a Failure Record.

• | The TCM stores DTC P1719 in TCM history.

### Conditions for Clearing the MIL/DTC

• | 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.

### Diagnostic Aids

Ask the customer about overloading the vehicle, exceeding the trailer towing limit, or towing in DRIVE (D).

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step tests for low fluid level, which may cause slipping, and result in an incorrect gear ratio.

2. This step tests for low line pressure.

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 |

1. Visually inspect the transmission cooling system for fluid leaks.
2. Repair leaks as necessary.

Refer to Fluid Leak Diagnosis .

Did you find and correct a condition?

Go to Step 12

Go to Step 3

3 | Inspect for correct transmission fluid level. Refer to Transmission Fluid Check . Is the action complete? | Go to Step 4 | --
4 |

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.

Important:

• | Before clearing the DTC, use the scan tool in order to record the PCM and the TCM Failure Records. Using the Clear Eng./Trans. DTC Info function erases the Failure Records from the powertrain control module (PCM) and the transmission control module (TCM).

• | Using the Clear Eng./Trans. DTC Info function erases stored DTCs in both the PCM and TCM.

3. Record the DTC Failure Records.
4. Clear the DTC.
5. Use the scan tool snapshot mode in order to record the Last Shift Status of each gear shift.
6. Drive the vehicle in DRIVE (D) and record the Last Shift Status of each gear shift.

Does the Last Shift Status of any gear shift indicate Long, Short, Tie-up, or Flare?

Go to Step 5

Go to Testing for Intermittent Conditions and Poor Connections

5 | Test for correct line pressure. Refer to Line Pressure Check . Is the action complete? | Go to Step 6 | --
6 |

1. Remove the transmission oil pan. Refer to Transmission Fluid Replacement .
2. Inspect the bottom of the pan for excessive sediment.

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:

• | Stuck 3-4, 4-5 Shift Solenoid Valve Assembly (54).

• | Stuck Reverse Shift Solenoid (S5) green (305)

• | Stuck Shift PC Solenoid (SLS) green (340)

• | Stuck TCC Lock Up PC Solenoid (SLU) black (339)

• | Stuck Shift Pressure Control Valve (430)

• | Stuck Shift Pressure Relay Valve (424)

• | Stuck Second Clutch Control Valve (446)

• | Stuck 1-2, Reverse Clutch Control Valve (411)

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 Cover Replacement . Is the action complete? | Go to Step 12 | --
10 | Inspect the following items:

• | Forward Clutch (552)

• | Direct Clutch (556)

• | 4-5 Clutch (577)

• | Second Coast Clutch (228)

• | 1-2, Reverse Clutch (620)

• | Low and Reverse Clutch (516)

• | 3rd Gear Band (16)

• | Second Clutch (217)

• | Second Clutch Sprag (503)

• | Low Clutch Sprag (523)

Did you find any of the above conditions?

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 |

1. Replace the AT fluid and filter. Refer to Output Speed Sensor Replacement .
2. Inspect for the correct AT fluid level.
3. Add new fluid as necessary.

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.

4. Use the scan tool in order to perform the following:

• | Reset oil life monitor to 100 percent

• | Clear TAPS

Did you complete the above procedures?

Go to Step 14

--

13 | Replace the transmission control module (TCM). Refer to Control Module References 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:

1. Select DTC.
2. Select Clear Info.
3. Operate the vehicle in DRIVE (D) in order to obtain a Good Last Shift Status for each gear shift.
4. Select Specific DTC.
5. Enter DTC P1719.

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 | System OK