Electrical OPEL FRONTERA 1998 Workshop Manual

7A1–34
TRANSMISSION CONTROL SYSTEM (4L30–E)
Diagnostic Aids
Refer to the accompanying chart for the normal range
signals and the illegal combinations.
Inspect the wiring for poor electrical connections at
the PCM and at the transmission 8–way connector.
Look for possible bent, backed out, deformed or
damaged terminals. Check for weak terminal tension
as well. Also check for a chafed wire that could short
to bare metal or other wiring. Inspect for a broken wire
inside the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Refer to the “Range Switch Logic Table” or
“Functional Test Procedure” for further information.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the indicated range signal to the
manual valve actually selected.5. This test checks for continuity between each
selected range switch connector terminals.
Range Switch Logic Table
Range
Range Switch Ping
PositionABCP(G)
ParkONOFFOFFON
ReverseONONOFFOFF
NeutralOFFONOFFON
D4OFFONONOFF
D3ONONONON
2ONOFFONOFF
LOFFOFFONON
IllegalOFFOFFOFFOFF
IllegalOFFOFFOFFON
DTC P0706 Transmission Range Switch (Mode Switch) Performance
StepActionYe sNo
1Perform the following checks:
The transmission linkage from the select lever to the manual
valve is adjusted properly.
Diagnostic circuit check.
Were the checks performed?
Go to Step 2—
21. Install the scan tool.
2. With the engine “off”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when the “Clear Info”
function is used.
3. Record the DTC “Failure Records”.
4. Select each transmission range: D1, D2, D3, D4, N, R, and P.
Does each selected transmission range match the scan tool
“Range Switch” display?
Go to Diagnostic
Aids
Go to Step 3
3Are all range switch pin displays incorrect?Go to Step 4Go to Step 5
4Check fuse and wiring to the 8–way connector terminal 5(D) for
opens.
Refer to Mode Switch in Automatic Transmission (4L30–E)
section.
If no problem was found, replace the range switch.
Is the replacement complete?
Go to Step 8—
51. Disconnect the 8–way range switch connector.
2. Using ohmmeter, check continuity between terminal 5(D) and
respectively terminals 3(G), 6(C), 7(B) and 8(A) of the 8–way
range switch connector.
3. Move shift selector lever through all positions and compare
results with “Range Switch Logic Table”.
Is one range switch pin display incorrect?
Go to Step 6Go to Step 7
6Check the affected wiring and connector, and repair.
Is the repair complete?
Go to Step 8—

7A1–36
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
D07RW029
Circuit Description
The TFT sensor is a thermister that controls the signal
voltage to the PCM. The PCM supplies a 5–volt reference
signal to the sensor on circuit RED/BLK–GRN/RED.
When the transmission fluid is cold, the sensor resistance
is high. The PCM detects high signal voltage. As the
transmission fluid temperature increases to the normal
operating temperature of 100
C (212F), the sensor
resistance becomes less and the voltage decreases to
1.5 to 2 volts. With transmission fluid over temperature
and DTC P0218 also set, check the transmission cooling
system.
This DTC detects a continuous short to ground in the TFT
signal circuit or the TFT sensor. This is a type “D” DTC.
Conditions For Setting The DTC
Battery voltage is between 10 and 16 volts.
Ignition is “on”.
TFT sensor indicating a voltage less than 0.4 volts.
All conditions met for 20 seconds.
Action Taken When The DTC Sets
Transmission default temperature will be:
80
C (176F) if engine temperature code is set.
100
C (212F) if engine temperature is warm.
80
C (176F) if engine run time is greater than 5
minutes.
21
C (69.8F) if engine run time is less than 5
minutes.
The PCM will not illuminate the CHECK TRANS
Lamp.
Conditions For Clearing The DTC
The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Check harness routing for a potential short to ground
in circuit RED/BLK–GRN/RED. Scan tool TFT
display should rise steadily to about 100
C (212F),
then stabilize.
Inspect the wiring for poor electrical connection at the
PCM and at the transmission 16–way connector.
Look for possible bent, backed out, deformed or
damaged terminals. Check for weak terminal tension
as we ll. A lso ch eck fo r a ch af e d w ire th at cou l d s ho r t
to bare metal or other wiring. Inspect for a broken wire
inside the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
The temperature to resistance value scale may be
used to test the TFT sensor at the various
temperature levels to evaluate the possibility of a
“skewed” (mis–scaled) sensor.
A “skewed” sensor could result in delayed garage
shifts or TCC complaints.
Verify customer driving habits, trailer towing, etc.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for a short to ground or a “skewed”
sensor.
4. This test checks for an internal fault within the
transmission by creating an open.

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–39
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input
D07RW029
Circuit Description
The TFT sensor is a thermistor that controls the signal
voltage to the PCM. The PCM supplies a 5–volt reference
signal to the sensor on circuit RED/BLK–GRN/RED.
When the transmission fluid is cold, the sensor resistance
is high and the PCM will sense high signal voltage. As the
transmission fluid temperature warms to the normal
operating temperature of 100
C (212F), the sensor
resistance becomes less and the voltage decreases to
about 1.5 to 2 volts.
This DTC detects a continuous open or short to power in
the TFT signal circuit or the TFT sensor. This is a type “D”
DTC.
Conditions For Setting The DTC
Battery voltage is between 10 and 16 volts.
Ignition is “on”.
TFT sensor indicating a voltage greater than 4.86
volts.
All conditions met for 20 seconds.
Action Taken When The DTC Sets
Transmission default temperature will be:
80
C (176F) if engine temperature code is set.
100
C (212F) if engine temperature is warm.
80
C (176F) if engine run time is greater than 5
minutes.
21
C (69.8F) if engine run time is less than 5
minutes.
The PCM will not illuminate the CHECK TRANS
Lamp.
Conditions For Clearing The DTC
The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Inspect the wiring for poor electrical connection at the
PCM and at the transmission 16–way connector.
Look for possible bent, backed out, deformed or
damaged terminals. Check for weak terminal tension
as we ll. A lso ch eck fo r a ch af e d w ire th at cou l d s ho r t
to bare metal or other wiring. Inspect for a broken wire
inside the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Scan tool displays transmission fluid temperature in
degrees. After transmission is operating, the
temperature should rise steadily to about 100
C
(212
F), then stabilize.
The temperature to resistance value scale may be
used to check the TFT sensor at the various
temperature levels to evaluate the possibility of a
“skewed” (mis–scaled) sensor.
A “skewed” sensor could result in hard shifts or TCC
complaints.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This check verifies problem in the TFT sensor circuit.
4. This test simulates a TFT sensor DTC P0712. If the
PCM recognizes the low signal voltage (high
temperature), and the scan tool displays 146
C
(295
F) or greater, the PCM and wiring are OK.

7A1–42
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0719 TCC Brake Switch Circuit High (Stuck On)
D07RW032
Circuit Description
The TCC brake switch is used to indicate brake pedal
status. The normally opened brake switch signal voltage
circuit is opened.
Brake switch supplies a B+ signal on circuit GRN/YEL to
the PCM when the brakes are applied. The PCM uses
this signal to deenergize the TCC solenoid when the
brakes are applied.
This DTC detects a closed brake switch during
accelerations. This is a type “D” DTC.
Conditions For Setting The DTC
No OSS DTCs P0722 or P0723.
The PCM detects a closed brake switch/circuit (12
volts) for 2 seconds, and the following events occur
seven consecutive times: vehicle speed is less than 8
km/h (5 mph); then vehicle speed is between 8 and 32
km/h (5 and 20 mph) for 4 seconds; then vehicle
speed is greater than 32 km/h (20 mph) for 4 seconds.
Action Taken When The DTC Sets
If throttle opening is greater than 10% and vehicle
speed is greater than 45 km/h (28 mph), then
disregard brake switch contingency for TCC off
mode.
The PCM will not illuminate the CHECK TRANS
Lamp.
Conditions For Clearing The DTC
The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Inspect the wiring for poor electrical connections at
the PCM and TCC brake switch. Look for possible
bent, backed out, deformed or damaged terminals.
Check for weak terminal tension as well. Also check
for a chafed wire that could short to bare metal or
other wiring. Inspect for a broken wire inside the
insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Check customer driving habits and/or unusual driving
conditions (i.e. stop and go, highway).
Check brake switch for proper mounting and
adjustment.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for voltage at the brake switch.
6. This test checks the brake switch.
9. This test checks circuit GRN/YEL at the PCM.

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–45
DTC P0722 Transmission Output Speed Sensor (OSS) Low Input
D07RW006
Circuit Description
Output speed information is provided to the PCM by the
OSS, which is a permanent magnet (PM) generator. The
PM generator produces a pulsing AC voltage. The AC
voltage level and number of pulses increases as the
speed of the vehicle increases. The PCM then converts
the pulsing voltage to output speed, which is used for
calculations. The vehicle speed can be displayed with a
scan tool.
This DTC detects a low output speed when there is a high
engine speed in a drive gear range. This is a type “C”
DTC.
Conditions For Setting The DTC
No MAP DTCs P0107 or P0108, P0106, P1106,
P1107.
No TPS DTCs P0122 or P0123.
Not in Park or Neutral.
TP angle is greater than 10%.
Engine vacuum is between 0 and 70kPa.
Engine speed is between 3,000 and 7,000 rpm.
Transmission output speed is less than 0 rpm.
All conditions met for 5 seconds.
Action Taken When The DTC Sets
Fixed to 4th gear.
Maximum line pressure.
Inhibit TCC engagement.
The PCM will illuminate the CHECK TRANS Lamp.
Conditions For Clearing The MIL/DTC
The PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.
The DTC can be cleared from the PCM history by
using a scan tool. The DTC will be cleared from
history when the vehicle has achieved 40 warmup
cycles without a failure reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
An OSS DTC P0722 will set when no output speed is
at detected at start off.
Inspect the wiring for poor electrical connection at the
PCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring. Inspect for a
broken wire inside the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
5. This test checks the OSS circuit.
6. This test checks the integrity of the OSS.
8. This test checks the 5–volt and ground circuit of the
PCM.

7A1–48
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0723 Transmission Output Speed Sensor (OSS) Intermittent
D07RW006
Circuit Description
Output speed information is provided to the PCM by the
OSS, which is a permanent magnet (PM) generator. The
PM generator produces a pulsing AC voltage. The AC
voltage level and number of pulses increases as the
speed of the vehicle increases. The PCM then converts
the pulsing voltage to output speed, which is used for
calculations. The vehicle speed can be displayed with a
scan tool.
This DTC detects a low output speed when there is a high
engine speed in a drive gear range. This is a type “C”
DTC.
Conditions For Setting The DTC
In Park or Neutral:
Transmission output speed change is greater than
10,000 rpm.
Conditions met for 6 seconds.
Engine running time is greater than 2 seconds.
Not in Park or Neutral:
Transmission output speed change is greater than
512 rpm.
Conditions met for 0.075 seconds
Engine running time is greater than 2 seconds.
Engine vacuum is less than 70 kPa.
Output speed is greater than 1,380 rpm for 1 second.
NORAW–NOLAST < 60 rpm for 6 seconds.
NORAW: Latest raw data of output shaft speed.
NOLAST: Filtered pervious data of output speed.
Action Taken When The DTC Sets
Fixed to 4th gear.
Maximum line pressure.
Inhibit TCC engagement.
The PCM will illuminate the CHECK TRANS Lamp.
Conditions For Clearing The MIL/DTC
The PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.
The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
A OSS DTC P0723 will set when output speed has
been detected and is lost.
Inspect the wiring for poor electrical connection at the
PCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring. Inspect for a
broken wire inside the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
5. This test checks the OSS circuit.
6. This test checks the integrity of the OSS.
8. This test checks the 5–volt and ground circuit of the
PCM.

7A1–54
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0748 Pressure Control Solenoid (PCS) (Force Motor) Circuit Electrical
D07RW008
Circuit Description
The PCS is a PCM–controlled device used to regulate
transmission line pressure. The PCM compares TPS
voltage, engine rpm, and other inputs to determine the
line pressure appropriate for a given load. The PCM will
regulate the pressure by applying a varying amperage to
the PCS. The applied amperage can vary from 0.1 to 1
amp, and is monitored by the PCM.
This DTC detects a continuous open or short to ground in
the PCS circuit or the PCS. This is a type “C” DTC.
Conditions For Setting The DTC
Battery voltage is between 10 and 16 volts.
The PCM detects that the different between
commanded and actual current is 200 milliampere
(mA) for over 1 second.
Action Taken When the DTC Sets
Maximum line pressure.
The PCM will illuminate the CHECK TRANS Lamp.
Conditions For Clearing The DTC/CHECK
TRANS Lamp
The PCM will turn “off” the CHECK TRANS Lamp
after three consecutive ignition cycles without a
failure reported.
The DTC can be cleared from PCM history by using a
scan tool.
The DTC will be cleared from memory when the
vehicle has achieved 40 warmup cycles without a
failure reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Inspect the wiring for poor electrical connection at the
PCM and at the transmission 5–way connector. Look
for possible bent, backed out, deformed or damaged
terminals. Check for weak terminal tension as well.
Also check for a chafed wire that could short to bare
m e t a l o r o t h e r w i r i n g . I n s p e c t f o r a b r o k e n w i r e i n s i d e
the insulation.
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the ability of the PCM to command
the PCS.
3. This test checks the PCS and internal wiring harness
for incorrect resistance.

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–55
DTC P0748 Pressure Control Solenoid (PCS) (Force Motor) Circuit Electrical
StepActionYe sNo
11. Install the scan tool.
2. With the engine “off”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when the “Clear Info”
function is used.
3. Record the DTC “Failure Records”.
4. While the engine is operating, put the transmission in Park.
5. Using the scan tool, apply 0.1 amp through 1.0 amp while
observing “PC Ref. Current” and “PC Act. Current”.
Is the “PC Act. Current” reading always within 0.16 amp?
Go to Diagnostic
Aids
Go to Step 2
21. Turn the ignition “off”.
2. Disconnect the transmission 5–way connector M–6.
3. Using the J39200 DVOM, measure the resistance between
terminals M6–2(B) and M6–1(E).
Is the resistance within 3–7 ohms?
Go to Step 6Go to Step 3
31. Remove the transmission oil pan. Refer to Solenoid (Adapter
Case Valve Body) in Automatic Transmission (4L30–E)
section.
2. Disconnect the internal wiring harness at the PCS.
3. Measure the resistance of the PCS.
Is the resistance within 3–7 ohms?
Go to Step 5Go to Step 4
4Replace the PCS.
Is the replacement complete?
Go to Step 9—
5Repair the internal wiring harness for an open.
Is the repair complete?
Go to Step 9—
6Inspect/repair circuits J3–E4, M6–2(B), J3–E3, and M6–1(E).
Was a problem found?
Go to Step 9Go to Step 7
7Inspect/repair circuits J3–E4, M6–2(B), J3–E3, and M6–1(E) for
a short to ground or poor connections.
Was a problem found?
Go to Step 9Go to Step 8
8Replace the PCM. Refer to Powertrain Control Module (PCM) in
Automatic Transmission (4L30–E) section.
Is the replacement complete?
Go to Step 9—
91. After the repair is complete, use the scan tool to select “DTC”,
then “Clear Info” function and ensure the following conditions
are met:
The PCS duty cycle is not at its electrical high or low limit.
2. Review the scan tool “DTC Info”.
Has the last test failed or is the current DTC displayed?
Begin diagnosis
again
Go to Step 1
Repair verified
Exit DTC table

7A1–56
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0753 Shift Solenoid A Electrical
D07RW009
Circuit Description
The shift solenoid A is a simple on/off solenoid
located in the main case valve body. The solenoid is
the normally closed type. In second or third gear, the
Powertrain Control Module (PCM) energizes the
solenoid to open a fluid inlet port. When the port is
open, fluid pressure actuates the shift valve.
The solenoid is activated by current. This current is
produced by applying a voltage to one side (the High
side) and a ground to the other side (Low side).
The High Side Driver (HSD) is a circuit of the PCM
that acts as a switch between the solenoids and the
supply voltage. The High side of the solenoid is
permanently supplied with voltage, except in
BACKUP MODE or when ignition is off the HSD is
turned off.
This DTC detects a continuous open or short to ground in
the shift solenoid A circuit or the shift solenoid A. This is a
type “C” DTC.
Conditions For Setting The DTC
Ignition is “on”, Engine “run”.
Battery voltage is between 10 and 16 volts.
The PCM commands the solenoid “on” and the
voltage remains high (B+) or the PCM commands the
solenoid “off” and the voltage remains low (zero
volts).
All conditions met for 0.33 seconds.
Action Taken When The DTC Sets
Maximum line pressure.
Immediate landing to 4th gear.
Inhibit TCC engagement.
The PCM will illuminate the CHECK TRANS Lamp.
Conditions For Clearing The MIL/DTC
The PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.
The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Inspect the wiring for poor electrical connection at the
PCM and at the transmission 16–way connector.
Look for possible bent, backed out, deformed or
damaged terminals. Check for weak terminal tension
as we ll. A lso ch eck fo r a ch af e d w ire th at cou l d s ho r t
to bare metal or other wiring. Inspect for a broken wire
inside the insulation.

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–57
When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.
An open ignition feed circuit can cause multiple DTCs
to set.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for power to the shift solenoid A
from the ignition through the PCM.
5. This test measures the resistance of the component.9. This test checks the function of the shift solenoid A
and the transmission internal wiring harness.
Shift Solenoid Status Chart
Gear
Shift solenoid AShift solenoid B
1stOFFON
2ndONON
3rdONOFF
4thOFFOFF
DTC P0753 Shift Solenoid A Electrical
StepActionYe sNo
11. Install the scan tool.
2. With the engine “on”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when the “Clear Info”
function is used.
3. Record the DTC “Failure Records”.
Were DTCs P0753, P0758, P1860 set?
Go to Step 2
Go to Diagnostic
Aids
21. Turn the ignition “on”.
2. Using the J39200 DVOM, measure the voltage between PCM
connector terminals J3–E14 and J2–C8 (GND).
Is the voltage within 10–12 volts?
Go to Step 3Go to Step 4
31. Turn the ignition “off”.
2. Disconnect the J3 (BLUE) PCM connector.
3. Turn the ignition “on”.
4. Using the J39200 DVOM, measure the voltage between PCM
connector terminals J3–F14 and ground.
Is the voltage within 10 – 12 volts?
Go to Step 10Go to Step 4
41. Turn the ignition “off”.
2. Disconnect the J3 (BLUE) PCM connector.
3. Using the J39200 DVOM, measure the resistance between
PCM connector terminals J3–E14 and J3–F14.
Is the resistance within 18 – 20 ohms?
Go to Step 5Go to Step 6
51. Disconnect the J1 (RED) and J2 (WHITE) PCM connectors.
2. Using the J39200 DVOM, check a continuity between PCM
terminals J3–F14 and ground.
Is there a continuity?
Go to Step 11Go to Step 7
61. Disconnect the 16–way harness connector H–53.
2. Using the J39200 DVOM, measure the resistance between
terminals H53–14 and H53–15.
Is the resistance within 18–20 ohms?
Go to Step 13Go to Step 8
7Using the J39200 DVOM, check a continuity between J3 (BLUE)
PCM terminal E14 and ground.
Is there a continuity?
Go to Step 12Go to Step 9
81. Disconnect the transmission main case 4 pin connector M–7.
2. Using the J39200 DVOM, measure the resistance between
terminals M7–3(D) and M7–4(C).
Is the resistance within 18–20 ohms?
Go to Step 14Go to Step 15