DTC P1855 Non-Europe or N. American Emissions
Circuit Description
The shift solenoids are 2 identical, normally open electronic exhaust valves that control upshifts and downshifts in all forward gear ranges. These shift solenoids work together in a combination of ON and OFF sequences to control the line pressure and shift mechanisms, such as clutches and brakes.
Solenoid 2 controls the high or low of the line pressure, the flow to each clutch valve, by the operation type, ON/OFF. For example, if solenoid 2 is ON, the line pressure will be low, 599-799 kPa (87-116 psi) (6-8 bar). If solenoid 1 is OFF, the line pressure will be high, 1 599-1 799 kPa (232-261 psi) (16-18 bar). Solenoid 2 controls the oil flow to the clutch valve E or the lock-up clutch valve by the ON/OFF signal.
The transmission control module (TCM) monitors numerous inputs to determine the appropriate solenoid state combination and transaxle gear for the vehicle operating conditions.
Conditions for Setting the DTC
| • | Solenoid wiring open |
| • | No DTC P1853, P1854. |
| • | Immediately after the above condition occurs |
Action Taken When the DTC Sets
| • | The hold lamp will blink. |
| • | The 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. |
| • | After the ignition is OFF/ON: 3rd gear by hydraulic control. P, R, and N are also possible. |
Conditions for Clearing the Hold Lamp/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 P1855 sets, the possible cause of the fault could be solenoid 2.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the solenoid 2 change ON/OFF? | -- | Go to Diagnostic Aids | Go to Step 3 |
3 |
Is the resistance within the specified values? | TFT 25°C (77°F) 6 ohms | Go to Step 7 | Go to Step 4 |
4 |
Is the resistance within the specified value? | 0 ohms | Go to Step 6 | Go to Step 5 |
5 |
Is the repair complete? | -- | System OK | -- |
6 | Replace the solenoid 2. Is the replacement complete? | -- | System OK | -- |
7 |
Is the resistance approximately equal to the specified value? | 0 ohms | Go to Step 9 | Go to Step 8 |
8 | Repair the transaxle wiring harness for an open. Is the repair complete? | -- | System OK | -- |
9 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the replacement complete? | -- | Go to Step 10 | -- |
10 |
Has the last test failed or is the current DTC displayed? | -- | Go to Step 2 | System OK |
DTC P1855 European and N. American Emissions
Circuit Description
The shift solenoids are 2 identical, normally open electronic exhaust valves that control upshifts and downshifts in all forward gear ranges. These shift solenoids work together in a combination of ON and OFF sequences to control the line pressure and shift mechanisms, such as clutches and brakes.
Solenoid 2 controls the high or low of the line pressure, the flow to each clutch valve, by the operation type, ON/OFF. For example, if solenoid 2 is ON, the line pressure will be low, 599-799 kPa (87-116 psi) (6-8 bar). Solenoid 1 is OFF, the line pressure will be high, 1 599-1 799 kPa (232-261 psi) (16-18 bar). Solenoid 2 controls the oil flow to the clutch valve E or the lock-up clutch valve by the ON/OFF signal.
The transmission control module (TCM) monitors numerous inputs to determine the appropriate solenoid state combination and transaxle gear for the vehicle operating conditions.
Conditions for Setting the DTC
| • | Solenoid wiring open |
| • | No DTC P1853, P1854. |
| • | Immediately after the above condition occurs |
Action Taken When the DTC Sets
| • | The malfunction indicator lamp (MIL) will illuminate. |
| • | The 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 the ignition is OFF/ON: 3rd gear by hydraulic control. P, R, and N are also possible. |
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 P1855 sets, the possible cause of the fault could be solenoid 2.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the solenoid 2 change ON/OFF? | -- | Go to Diagnostic Aids | Go to Step 3 |
3 |
Is the resistance within the specified values? | TFT 25°C (77°F) 6 ohms | Go to Step 7 | Go to Step 4 |
4 |
Is the resistance within the specified value? | 0 ohms | Go to Step 6 | Go to Step 5 |
5 |
Is the repair complete? | -- | System OK | -- |
6 | Replace the solenoid 2. Is the replacement complete? | -- | System OK | -- |
7 |
Is the resistance approximately equal to the specified value? | 0 ohms | Go to Step 9 | Go to Step 8 |
8 | Repair the transaxle wiring harness for an open. Is the repair complete? | -- | System OK | -- |
9 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the replacement complete? | -- | Go to Step 10 | -- |
10 |
Has the last test failed or is the current DTC displayed? | -- | Go to Step 2 | System OK |
