For 1990-2009 cars

## DTC P1868 Non-Europe or N. American Emissions

### Circuit Description

The pressure control valves 3, 4, 5, and 6 are precision electronic pressure regulators that control the operation of the clutches, brakes and lock-up clutch.

The valve reduces the system pressure with which the downstream solenoid valves and electrical pressure regulating valves are supplied. It is possible to use smaller solenoid valves as a result. The pressure control valves require a constant input pressure.

### Conditions for Setting the DTC

• | Output voltage of the solenoid valve 6 at ON is 12 volts.

• | No DTC P1867, P1869.

• | Immediately after the above condition occurs.

### Action Taken When the DTC Sets

• | The hold lamp will blink.

• | The transmission control module (TCM) will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.

• | Adopt Emergency/Substitute mode and constant 4th gear by hydraulic control.

• | After ignition OFF/ON : 3rd gear by hydraulic control. P, R and N also possible.

• | Power supply cut off to the pressure control solenoid valve.

### Conditions for Clearing the Hold Lamp/DTC

• | The hold lamp will turn OFF when the malfunction has not occurred after 3 ignition cycles.

• | A history DTC will clear after 40 consecutive warm-up cycles without a fault.

• | Using a scan tool can clear history DTCs.

### Diagnostic Aids

When DTC P1868 sets, the possible cause of fault could be the TCM.

#### DTC P1868

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

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Select "Actuating" on the scan tool.
4. Actuate the pressure control valve 6 ON/OFF.

Does the valve change ON/OFF?

--

Go to Diagnostic Aids

Go to Step 3

3 |

1. Remove the oil pan.
2. Disconnect the wiring connector of pressure control solenoid valve 6.
3. Turn the ignition ON, with the engine OFF.
4. Measure the voltage of the wiring connector terminal 2 to the solenoid valve 6.

Is the voltage within the specified value?

11-14 V

Go to Step 4

Go to Step 5

4 | Repair the internal line for valve 6 for a short to power. Is the repair complete? | -- | System OK | --
5 | Replace solenoid valve 6. Is the replacement complete? | -- | Go to Step 6 | --
6 | Test if any DTCs are set. Are any DTCs displayed that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK

## DTC P1868 European and N. American Emissions

### Circuit Description

The pressure control valves 3, 4, 5, and 6 are precision electronic pressure regulators that control the operation of the clutches, brakes and lock-up clutch.

The valve reduces the system pressure with which the downstream solenoid valves and electrical pressure regulating valves are supplied. It is possible to use smaller solenoid valves as a result. The pressure control valves require a constant input pressure.

### Conditions for Setting the DTC

• | Output voltage of the solenoid valve 6 at ON is 12 volts.

• | No DTC P1867, P1869.

• | Immediately after the above condition occurs.

### Action Taken When the DTC Sets

• | The malfunction indicator lamp (MIL) is illuminated.

• | The transmission control module (TCM) will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.

• | Adopt Emergency/Substitute mode and constant 4th gear by hydraulic control.

• | After ignition OFF/ON : 3rd gear by hydraulic control. P, R and N also possible.

• | Power supply cut off to the pressure control solenoid valve.

### Conditions for Clearing the MIL/DTC

• | The MIL will turn OFF when the malfunction has not occurred after 3 ignition cycles.

• | A history DTC will clear after 40 consecutive warm-up cycles without a fault.

• | Using a scan tool can clear history DTCs.

### Diagnostic Aids

When DTC P1868 sets, the possible cause of fault could be the TCM.

#### DTC P1868

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

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Select "Actuating" on the scan tool.
4. Actuate the pressure control valve 6 ON/OFF.

Does the valve change ON/OFF?

--

Go to Diagnostic Aids

Go to Step 3

3 |

1. Remove the oil pan.
2. Disconnect the wiring connector of pressure control solenoid valve 6.
3. Turn the ignition ON, with the engine OFF.
4. Measure the voltage of the wiring connector terminal 2 to the solenoid valve 6.

Is the voltage within the specified value?

11-14 V

Go to Step 4

Go to Step 5

4 | Repair the internal line for valve 6 for a short to power. Is the repair complete? | -- | System OK | --
5 | Replace solenoid valve 6. Is the replacement complete? | -- | Go to Step 6 | --
6 | Test if any DTCs are set. Are any DTCs displayed that have not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK