Expand AllEight pressure switches are installed in the valve body. The oil passages in the valve body are switched according to the operation status of each solenoid, each shift valve, and each control valve etc., and the pressure switches are switched ON or OFF. Pressure switch 1 operates according to the status of solenoid SL1 and control valve No. 1, pressure switch 2 operates according to the status of solenoid SL2 and control valve No. 2, and pressure switch 7 operates according to the status of solenoid SL3 and control valve No. 3. The transmission control computer ASSY puts out diagnostic codes when trouble occurs in this PSW1 signal system, PSW2 signal system, PSW7 signal system or in the solenoid or control valve system.
| DTC No. |
|
Inspection part |
| P0746/31 |
|
|
| P0776/32 |
|
|
| P2757/33 |
|
|
| DTC No. |
|
Inspection part |
| P0746/31 |
|
|
| P0776/32 |
|
|
| P2757/33 |
|
|
Detail
- Confirm output of P0748/25 (SL1 solenoid system), P0778/26 (SL2 solenoid system), and P2759/27 (lock-up solenoid system) in addition to DTC P0746/31, P0776/32 and P2757/33.
Standard:
Inspection result Step Only output of DTC P0746/31, P0776/32 and P2757/33 To step A Output of DTC 0746/31, P0776/32, P2757/33 and other diagnostic codes To step B
In case of output of a diagnostic code other than DTC P0746/31, P0776/32 and P2757/27, perform trouble-shooting for that diagnostic code first.
B
To the related diagnostic code chart (refer to page for the outline)A
Proceed to [2]INSPECT TRANSMISSION CONTROL COMPUTER ASSY BY ITSELF (INSPECT VOLTAGE)
- Set the ignition switch to ON.
- Check the voltage between the terminals of the transmission control computer ASSY. (Refer to page for the terminal layout.)
Standard:
Terminal No.
(terminal symbol)Measuring condition Voltage [V] C6 (PSW1) ↔ B8 (GND1) P range
(Pressure switch 1 OFF)12-32 C12 (PSW2) ↔ B8 (GND1) D range
(Pressure switch 2 OFF)12-32 A11 (PSW7) ↔ B8 (GND1) P range
(Pressure switch 7 OFF)12-32
Inspect and replace the transmission control computer ASSY.
Proceed to [3]INSPECT WIRE HARNESS AND CONNECTOR (TRANSMISSION CONTROL COMPUTER ASSY - TRANSMISSION WIRE)
- Disconnect connectors A and B of the transmission wire.
- Set the ignition switch to ON.
- Check the terminal voltage between the connector on the wire harness side of the transmission wire and body earth.
Standard:
Terminal No.
(terminal symbol)Measuring condition Voltage [V] A1 (PSW1) ↔ Body earth P range
(Pressure switch 1 OFF)12-32 A7 (PSW2) ↔ Body earth D range
(Pressure switch 2 OFF)12-32 B1 (PSW7) ↔ Body earth P range
(Pressure switch 7 OFF)12-32
Repair or replace wire harness and connector.
Proceed to [4]INSPECT TRANSMISSION WIRE BY ITSELF (PSW1, PSW2, PSW7)
- Disconnect the two transmission wires.
- Check for conductivity between the terminals.
Standard:
Terminal No. (terminal symbol) Conductivity A1 (PSW1) ↔ PSW1 Yes A7 (PSW2) ↔ PSW2 Yes B1 (PSW7) ↔ PSW7 Yes
Repair or replace the transmission wire.
Replace the automatic transmission ASSY.
- Confirm the DTC P0776/32 is inactive
- Start the engine and let it idling condition.
- Verify the DTC P0776/32 is inactive.
- DTC Clear
- Clear the DTC with Hino DX
- Confirm the same DTC is not reoccurred
- P0776/32 is reoccurF Return to first process
- Other DTC appearF Refer to concerned Trouble shooting
Complete
