Toyota RM787U, Руководство по обслуживанию и ремонту

Страница: 406 / 1976

Position
D
NORMAL
Solenoid valve
No.2
ON
Gear
No.1
L
2
ON ON
OFF
ON OFF
OFF OFF
OFF ON
ON ON
OFF ON
ON OFF
ON ON
1st
2nd
3rd
O/D
1st
2nd
3rd
1st
2nd
Solenoid valve
No.1 No.2
X
X
X
X
X
X
X
X
X
ON
ON
ON
OFF
ON
ON
ON
OFF
ON
Gear
3rd
3rd
3rd
O/D
3rd
3rd
3rd
1st
2nd
No.1 No.2
Solenoid valve
Gear
1st ON X
X
X
X
X
X
X
X
X
OFF
OFF
OFF
ON
ON
OFF
OFF
ON
SHIFT SOLENOID NO.1
MALFUNCTIONING SHIFT SOLENOID NO.2
MALFUNCTIONING
O/D
O/D
O/D
1st
O/D
O/D
1st
1st
MALFUNCTIONING
BOTH SOLENOID
Gear when shift selector is
manually operated
O/D
O/D
O/D
O/D
1st
1st
X: Malfunctions
O/D
O/D
O/D
- DIAGNOSTICS AUTOMATIC TRANSAXLE
DI-181
335
Author: Date:
2001 SIENNA (RM787U)
DTC P0753, P0758 Shift Solenoid A/B Electrical Malfunc-
tion (Shift Solenoid Valve No.1/No.2)
CIRCUIT DESCRIPTION
Shifting from 1st to O/D is performed in combination with ON and OFF of the shift solenoid valves No.1 and
No.2 controlled by ECM. If an open or short circuit occurs in either of the shift solenoid valves, the ECM con-
trols the remaining normal shift solenoid valve to allow the vehicle to be operated smoothly (Fail safe func-
tion).
Fail Safe Function:
If either of the shift solenoid valve circuits develops an open or short, the ECM turns the other shift solenoid
ON and OFF to shift to the gear positions shown in the table below. The ECM also turns the shift solenoid
valve SL OFF at the same time. If both solenoids are malfunctioning, hydraulic control cannot be performed
electronically and must be done manually.
Manual shifting as shown in the following table must be done (In the case of a short circuit, the ECM stops
sending current to the short circuited solenoid).
HINT:
Check the shift solenoid valve No.1 when DTC P0753 is output and check the shift solenoid valve No.2 when
DTC P0758 is output.
DTC No. DTC Detecting Condition Trouble Area
P0753
P0758
The ECM checks for an open or short circuit in the shift sole-
noid valve No.1 and/or No.2 circuit when it changes.
The ECM records DTC P0753 or P0758 if condition (a) or (b) is
detected once, but it does not light up MIL.
After ECM detects condition (a) or (b) continuously 8 times or
more in a trip and the MIL lights up.
(a) When the solenoid is energized, the solenoid resistance is
8
Ω
or less and is counted.
(b) When the solenoid is not energized, the solenoid resistance
is 100 k
Ω
or more and is counted.
Open or short in shift solenoid valve No.1/No.2 circuit
Shift solenoid valve No.1/No.2
ECM
DI0CT-06