Opel Frontera UBS. Manual - part 571

7A1–62 TRANSMISSION CONTROL SYSTEM (4L30–E)

DTC P0758 Shift Solenoid B Electrical  (Cont’d)

Step

No

Yes

Action

21

The wiring harness between PCM connector terminal J3–E14
and transmission main case connector terminal M7–4(C) is
shorted to ground.

Was a problem found and corrected?

Go to Step 25

—

22

The wiring harness between transmission 16–way connector
terminal H53–16 and transmission main case connector terminal
M7–1(A), or between H53–15 and M7–4(C) is open.

Was a problem found and corrected?

Go to Step 25

—

23

The internal wiring harness from the shift solenoid B is open, or
the shift solenoid B is faulty.

Was a problem found and corrected?

Go to Step 25

—

24

Replace the PCM.

Is the replacement complete?

Go to Step 25

—

25

1. After the repair is complete, use the scan tool to select “DTC”,

then “Clear Info” function and operate the vehicle under the
following conditions:

D

The shift solenoid B is commanded “on” and voltage drop to
zero.

D

The shift solenoid B is commanded “off” and voltage
increases to B+.

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

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–63

DTC P1790 ROM Transmission Side
Bad Check Sum

Circuit Description

Transmission Side Read Only Memory (ROM) and
Electronically Erasable Programmable Read Only
Memory (EEPROM) is an electronic circuit that controls
the transmission control in the Powertrain Control Module
(PCM).
This DTC detects a check sum error.  This is a type “C”
DTC.

Conditions For Setting The DTC

D

Detects check sum error for 1 second.

Action Taken When The DTC Sets

D

Maximum line pressure.

D

Immediate landing to 4th gear.

D

Inhibit TCC engagement.

D

The PCM will illuminate the CHECK TRANS Lamp.

Conditions For Clearing The MIL/DTC

D

The PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.

D

The DTC can be cleared from the PCM history by
using a scan tool.  

D

The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

D

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.

DTC P1790 ROM Transmission Side Bad Check Sum 

Step

Action

Yes

No

1

1. 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”.

Was DTC P1790 set?

Go to Step 4

Go to Step 2

2

Was DTC P1792 set?

Go to Step 3

—

3

1. Remove the PCM. Refer to Powertrain Control Module (PCM)

in Automatic Transmission (4L30–E) section.

2. Using the ITCS, make a reprogramming the transmission

EEPROM.

Was the reprogramming complete?

Go to Step 5

—

4

Replace the PCM.

Is the replacement complete?

Go to Step 5

—

5

1. After the repair is complete, use the scan tool to select “DTC”,

then “Clear Info” function and operate the vehicle.

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

7A1–64 TRANSMISSION CONTROL SYSTEM (4L30–E)

DTC P1792 EEPROM Transmission
Side Bad Check Sum

Circuit Description

Transmission Side Read Only Memory (ROM) and
Electronically Erasable Programmable Read Only
Memory (EEPROM) is an electronic circuit that controls
the transmission control in the Powertrain Control Module
(PCM).
This DTC detects a check sum error.  This is a type “C”
DTC.

Conditions For Setting The DTC

D

Detects check sum error for 1 second.

Action Taken When The DTC Sets

D

Maximum line pressure.

D

Immediate landing to 4th gear.

D

Inhibit TCC engagement.

D

The PCM will illuminate the CHECK TRANS Lamp.

Conditions For Clearing The MIL/DTC

D

The PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.

D

The DTC can be cleared from the PCM history by
using a scan tool.  

D

The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

D

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.

DTC P1792 EEPROM Transmission Side Check Bad Check Sum 

Step

Action

Yes

No

1

1. 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”.

Was DTC P1790 set?

Go to Step 4

Go to Step 2

2

Was DTC P1792 set?

Go to Step 3

—

3

1. Remove the PCM. Refer to Powertrain Control Module (PCM)

in Automatic Transmission (4L30–E) section.

2. Using the ITCS, make a reprogramming the transmission

EEPROM.

Was the reprogramming complete?

Go to Step 5

—

4

Replace the PCM.

Is the replacement complete?

Go to Step 5

—

5

1. After the repair is complete, use the scan tool to select “DTC”,

then “Clear Info” function and operate the vehicle.

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

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–65

DTC P1835 Kickdown Switch Always On

D07RW033

Circuit Description

D

When the driver presses the accelerator pedal down
fully, the kickdown switch closes, sending a ground
signal to the Powertrain Control Module (PCM).

D

This information is used to perform shifts at high
engine speed.

D

When the kickdown switch is closed, the Throttle
Position Sensor (TPS) is already is at 100%.

D

This DTC detects a closed kickdown switch when TP
angle is less than 70%.

D

This is a type “D” DTC.

Conditions For Setting The DTC

D

No TPS DTCs P0122 or P0123.

D

TP angle is less than 70%.

D

Kickdown switch is “on”.

D

All conditions met for 1 second.

Action Taken When The DTC Sets.

D

Kickdown mode control is off.

D

The PCM will not illuminate the CHECK TRANS
Lamp.

Conditions For Clearing The DTC

D

The DTC can be cleared from the PCM history by
using a scan tool.  

D

The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

D

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

D

Check the wiring harness for a short to ground
between the PCM and kickdown switch.

D

Check the kickdown switch for failure.

D

Check kickdown adjustment.

Test Description

The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks for short to ground or kickdown

switch failure.

4. This test checks for regulation kickdown switch.