OPEL FRONTERA 1998 Workshop Manual

7A–40 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0743 (FLASHING CODE 33) TORQUE CONVERTER CLUTCH CONTROL LOCK-UP (ON/
OFF) SOLENOID FA I L U R E ( S L )
D07RY00047Circuit description:
The lock-up solenoid SL of the torque converter clutch
(TCC) controls the lock-up clutch by a signal according to
the lock-up range judgement of the TCM when the
vehicle runs.
This function can improve the fuel consumption to almost
the same extent as the manual transmission. The lock-up
solenoid SL is put into B+ by the TCM, so that the
solenoid is actuated with the result of lock-up.
Fail-safe control:
The TCM controls fail-safe by detecting SL solenoid
fai lu re.
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
• If + B short failure is detected, keeps 1st gear when
the vehicle speed calculated by output revolution
sensor is less than 10km/h to prevent stall.
(Canceled at more than 15km/h)
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:
NoneReversion conditions from fail-safe:
When a normal condition is judged by rechecking on the
state of lock-up ON/OFF
Test description:
The following numbers correspond to circled numbers on
the diagnostic char t.
(1) When the key is ON, the voltage between the TCM
connector terminals (C78-12) and (C78-15 or 19) is
1.0 V or less.
(2) When the gear is of the 2nd speed in the D range
and the throttle opening is about 50% at a higher
speed than about 40km/h, the TCM supplies 8 to 16
V, so that the solenoid is actuated with the result of
lock-up.
(3) The resistance range of the solenoid is 11 to 15
.
Diagnostic aids:
In case of faulty connection, open or shorted circuit. to
the TCM terminal (C78-12), DTC P0743 is displayed. A
intermittent failure may be caused by a poor connection,
rubbed through wire insulation or a wire broke inside the
insulation.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–41
DTC P0743 (FLASHING CODE 33) TORQUE CONVERTER CLUTCH CONTROL LOCK-UP (ON/OFF) SOLENOID
FAILURE (SL)
DTCP0743

7A–42 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0748 (FLASHING CODE 35) PRESSURE CONTROL SOLENOID FAILURE (STH)
D07RY00047Circuit description:
The pressure control solenoid is a PWM duty control
solenoid located in the valve body.
The pressure control solenoid is a TCM-controled device
used to regulate transmission throttle pressure by
energizing current from the TCM.
Fail-safe control:
The TCM controls fail-safe by detecting pressure control
solenoid failure.
Failure detection:
IG shor t failure
• When the feedback A/D value is more than 1020 for
500 milli-second continuously.
• Detection inhibit condition: Prohibition during 1 second
after reversion from open failure, because the
possibility of the mis-detection is high.
Open failure (Including GND Shor t)
• When the feedback A/D value is less than 15 for more
than 70 milli-second continuously, judges as faliure,
and turns the current of target output off, after 1.5
second passed turns the current of target value to
normal. The A/D value is checked, and this operation
is repeated during 70 milli-second again.
• When it continues for 12.5 second in total.
Contents of control:
At failure detection
• Lock-up control inhibit
• Up hill and down hill control inhibit
• Squat control inhibit
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
W h e n I G sh o r t fa i l u re ꞏꞏꞏT h e fe e d ba ck A / D va l u e i s
less than 1020 for 1 second continuously.
W h e n o p e n fa i l u re ꞏꞏꞏD e t e c t i o n c r i t e r i a i s n o t s a t i s f i e d
or the feedback A/D value is more than 15 for 1
second continuously.
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) The solenoid resistance is within the range of 5 to
5.6
.
(2) This test checks for shor ted circuit at the TCM.
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.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–43
DTC P0748 (FLASHING CODE 35) PRESSURE CONTROL SOLENOID FAILURE (STH)
DTCP0748

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

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

7A–46 AUTOMATIC TRANSMISSION (AW30-40LE)
DTC P0753 (FLASHING CODE 31) SOLENOID 1 FAILURE (S1)
DTCP0753

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–47
MEMO

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.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–49
DTC P0758 (FLASHING CODE 32) SOLENOID 2 FAILURE (S2)
DTCP0758