Opel Frontera UBS. Manual - part 2544

AUTOMATIC TRANSMISSION (AW30-40LE)

7A–39

DTC P0727 (FLASHING CODE 13) ENGINE REVOLUTION SIGNAL FAILURE (NE)

DTCP0727

7A–40

AUTOMATIC TRANSMISSION (AW30-40LE)

DTC P0743 (FLASHING CODE 33) TORQUE CONVERTER CLUTCH CONTROL LOCK-UP (ON/

OFF) SOLENOID FAILURE (SL)

D07RY00047

Circuit 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
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

• 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:
None

Reversion 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 chart.

(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

Ω

.

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)

D07RY00047

Circuit 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 short 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 Short)

• 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

When IG short failure···The feedback A/D value is
less than 1020 for 1 second continuously.
When open failure···Detection criteria is not satisfied
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 chart.

(1) The solenoid resistance is within the range of 5 to

5.6

Ω

.

(2) This test checks for shorted 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.