Page 5825 of 6000
7A–44 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0753 (FLASHING CODE 31) SOLENOID 1 FAILURE (S1)
D07RY00047Circuit description:
The shift solenoid S1 changes the hydraulic route with
the signals from the TCM according to the vehicle speed
and the throttle opening to control shifting. When the
solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.
Fail-safe control:
The TCM controls fail-safe by detecting S1, S2 shift
solenoid failure.
Failure detection:
GND SHORT detection
• When SHORT detection continues for 0.3 sec.
• When SHORT failure detection continues 8 times.
Open detection
• When OPEN detection continues for 0.5 sec.
• When OPEN failure detection continues 8 times.
Contents of control:
At failure detection
• Lock-up control inhibit
• Up hill and down hill control inhibit
• Squat control inhibit
Page 5826 of 6000

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–45
• Changes solenoid output pattern as following figure
The shift theory at shift solenoid failure
At failure decision
Executes following items in addition to above control
items at failure detection.
•Turns Solenoid power supply OFF
•Blinks "CHECK TRANS" lamp
•Stores the failure information in failure-memory
*Prohibits failure detection of S1, S2, SL, STH,
Selector position switch, and Oil temp. sensor.
Conditions of turning "CHECK TRANS" off:
Turns "CHECK TRANS" lamp off after ignition is turned
ON
OFF ON.
Reversion conditions from fail-safe:
At failure detection
When a normal judgment is obtained by rechecking
during shifting.
At failure decision
Recovers at the same time as the conditions of
turning “CHECK TRANS” lamp off are satisfied.
Test description:
The following numbers correspond to circled numbers on
the diagnostic char t.
(1) With the key "ON", the voltage between the TCM
terminals (C78-4) and (C78-15 or 19) is 8 to 16V.
(2) When the driving wheels revolve with the 3rd speed
gear, the voltage is 1 V or less.
(3) The solenoid resistance is within the range of 11 to
15
.
Diagnostic aids:
In case of faulty connection, open or shor ted circuit to
the TCM terminal (C78-4), DTC P0753 is displayed. A
intermittent failure may be caused by a poor connection,
rubbed through wire insulation or a wire broke inside the
insulation.Shift
lever
Po s i t i o nNormal S1 failure S2 filure S1 and S2 failure
Gear S1 S2 Gear S1 S2 Gear S1 S2 Gear S1 S2
D1
3
1
O/D 2O/D3
O/DO/D
213
1
3 2O/D3
L1313
2O/D
Page 5827 of 6000
7A–46 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0753 (FLASHING CODE 31) SOLENOID 1 FAILURE (S1)
DTCP0753
Page 5828 of 6000
AUTOMATIC TRANSMISSION (AW30-40LE) 7A–47
MEMO
Page 5829 of 6000

7A–48 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0758 (FLASHING CODE 32) SOLENOID 2 FAILURE (S2)
D07RY00047Circuit description:
The solenoid S2 changes the hydraulic route with the
signals from the TCM according to the vehicle speed and
the throttle opening to control shifting. When the solenoid
S1 or S2 fails, the hydraulic circuit is mechanically
operated as a backup.
Fail-safe control:
The TCM controls fail-safe by detecting S1, S2 shift
solenoid failure.
Failure detection:
GND SHORT detection
• When SHORT detection continues for 0.3 sec.
• When SHORT failure detection continues 8 times.
Open detection
• When OPEN detection continues for 0.5 sec.
• When OPEN failure detection continues 8 times.
Contents of control:
At failure detection
• Lock-up control inhibit
• Up hill and down hill control inhibit
• Squat control inhibit
• Changes solenoid output pattern as "The shift theory
at shift solenoid failure". (See DTC P0753)
At failure decision
Executes following items in addition to above control
items at failure detection.
• Turns Solenoid power supply OFF
• Blinks "CHECK TRANS" lamp
• Stores the failure information in failure-memory
*Prohibits failure detection of S1, S2, SL, STH,Selector position switch, and Oil temperature sensor.
Conditions of turning "CHECK TRANS" off:
Turns "CHECK TRANS" lamp off after ignition is turned
ON
OFF ON.
Reversion conditions from fail-safe:
At failure detection
When a normal judgment is obtained by rechecking
during shifting.
At failure decision
Recovers at the same time as the conditions of
turning “CHECK TRANS” lamp off are satisfied.
Test description:
The following numbers correspond to circled numbers on
the diagnostic char t.
1 With the key "ON", the voltage between the TCM
terminals (C78-3) or (C78-15 or 19) is 1V or less.
2 When the driving wheels revolve with the 2nd
speed gear, the voltage is 8 to 16V.
3 The resistance of the solenoid is in the range of
11 to 15
.
Diagnostic aids:
In case of faulty connection, open or shor ted circuit to the
TCM terminal (C78-3), DTC P0758 is displayed. A
intermittent failure may be caused by a poor connection,
rubbed through wire insulation or a wire broken inside
the insulation.
Page 5830 of 6000
AUTOMATIC TRANSMISSION (AW30-40LE) 7A–49
DTC P0758 (FLASHING CODE 32) SOLENOID 2 FAILURE (S2)
DTCP0758
Page 5831 of 6000

7A–50 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P1121 (FLASHING CODE 23) ANALOG THROTTLE SIGNAL FAILURE (VREF, VGND)
D07RY00023Circuit description:
When the signal of the engine throttle position sensor
located on the accelerator pedal is supplied to the
transmission TCM, the TCM judges the opening
condition of the throttle.
The shift point of the transmission is determined by this
opening condition of the throttle.
Fail-safe control:
The TCM controls fail-safe by detecting analog throttle
signal (VREF, VGND) failure.
Failure detection:
• When the Vref input voltage is detected more than
5.55V or less than 4.45V.
• When the Vgnd input voltage is detected more than
0.40V or less than -0.40V.
• When the failure criteria is continuously for 1.0 sec.
Contents of control:
At failure detection
• Judges throttle opening of linear sensor (Vth) as
Vref:5V, Vgnd:0V
• Throttle learning control inhibit
• Up hill and down hill control inhibit
At failure decision
Executes following items in addition to above control
items at failure detection.
• Stores the failure information in failure-memory
Conditions of turning “CHECK TRANS” lamp off:
None
Reversion conditions from fail-safe:
At failure detection
When the Vref input voltage is detected less than 5.55 V
and more than 4.45 V.
When the Vgnd input voltage is detected less than 0.40 V
and more than -0.40 V.
At failure decision
• Recovers when judged 0km/h by output revolutionsensor after the Vref input voltage is detected less
than 5.55V and more than 4.45V.
(however, uses 0 km/h judgment by back-up vehicle
speed at output revolution failure)
• Recovers when judged 0km/h by output revolution
sensor after the Vgnd input voltage is detected less
than 0.40V and more than -0.40V.
(however, uses 0 km/h judgment by back-up vehicle
speed at output revolution failure)
Test description:
The following numbers correspond to circled numbers on
the diagnostic char t.
(1) Check the power supply voltage (4.75-5.25V) of
throttle position sensor.
Diagnostic aids:
An intermittent may be caused by a poor connection,
rubbed through wire insulation or a wire broken inside
the insulation. Inspect related harness connector for
backed out terminals, improper mating, broken locks,
improperly formed or damaged terminals, poor terminal
to wire connection and damaged harness.
Page 5832 of 6000
AUTOMATIC TRANSMISSION (AW30-40LE) 7A–51
DTC P1121 (FLASHING CODE 23) ANALOG THROTTLE SIGNAL FAILURE (VREF, VGND)
DTCP1121