Opel Frontera UBS. Manual - part 1506

7A1–54 TRANSMISSION CONTROL SYSTEM (4L30–E)

Conditions For Clearing The DTC/CHECK
TRANS Lamp

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 PCM memory by using
a scan tool.  

D

The DTC can also be cleared from memory when the
vehicle has made 40 warmup cycles without a failure
reported.

D

The PCM will cancel the DTC Actions Taken items
when the fault conditions no longer exist and the
ignition is cycles “off” long enough to power down the
PCM.

Diagnostic Aids

D

Check for intermittent output speed sensor circuit
problems.

D

Check for possible incorrect calibration. (PCM part
No., tire specification, and rear axle ratio)

Test Description

The numbers below refer to the step numbers on the
diagnostic chart:
2. This step checks for possible low fluid level causing

slipping resulting in an undefined gear ratio.

3. This step checks for correct gear ratios for

commanded gears.

4. This step checks for low line pressure.

DTC P0730 Transmission Incorrect Gear Ratio 

Step

Action

Yes

No

1

Visually inspect the transmission cooling system for fluid leaks.

D

Refer to Chart 16: Possible Causes of Transmission Fluid
Leaks of Mechanical/Hydraulic Diagnosis Symptoms Index in
Automatic Transmission (4L30–E) section

Was condition found and corrected?

Go to Step 6

Go to Step 2

2

Refer to Checking Transmission Fluid Level and Condition in
Automatic Transmission (4L30–E) section.

Has transmission fluid checking procedure been performed?

Go to Step 3

Go to Checking

Transmission

Fluid Level and

Condition in

Automatic

Transmission

(4L30–E) section

3

1. Install the scan tool.
2. Turn the ignition switch to the “on” position.
3. Engine not running.

NOTE: Before clearing DTC(s) use the scan tool to record the
“Failure Records” for reference, as data will be lost when the “Clear
Info” function is used.

4. Record the Failure Record data.
5. Use the scan tool snapshot mode to record transmission gear

ratios.

6. Drive vehicle in transmission gear ranges L, 2, 3, and D with

the engine speed is greater than 3,500 rpm for 5.5 seconds.

7. Record each transmission gear.

1st:2.73 – 2.99
2nd:1.54 – 1.71
3rd:0.93 – 1.05
4th:0.66 – 0.78

Does commanded gear ratio match ranges as shown?

Refer to

Diagnostic Aids

Go to Step 4

4

Perform line pressure check.

D

Refer to Line Pressure Test in Automatic Transmission
(4L30–E) section.

Was condition found and corrected?

Go to Step 6

Go to Step 5

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–55

DTC P0730 Transmission Incorrect Gear Ratio  (Cont’d)

Step

No

Yes

Action

5

Check for possible clutch slippage.

D

Refer to Chart 6: Diagnostic Trouble Code (DTC) P0730 of
Mechanical/Hydraulic Diagnosis Symptoms Index in
Automatic Transmission (4L30–E) section.

Was condition found and corrected?

Go to Step 6

—

6

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

then “Clear info” function.

2. Operate the vehicle under the following conditions:

D

Drive the vehicle in D4 with the engine speed greater than
3,500 rpm to obtain anyone of the following gear ratios for
seven seconds.

1st 1:2.73 – 1:2.99

2nd 1:1.54 – 1:1.71

3rd 1:0.93 – 1:1.05

4th 1:0.66 – 1:0.78

Has the  last test failed?

Begin diagnosis

again

Go to Step 1

Repair verified
Exit DTC table

7A1–56 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

D

Battery voltage is between 10 and 16 volts.

D

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

D

Maximum line pressure.

D

The PCM will illuminate the CHECK TRANS Lamp.

Conditions For Clearing The DTC/CHECK
TRANS Lamp

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 PCM history by using a
scan tool.  

D

The DTC will be cleared from memory 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

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
metal or other wiring.  Inspect for a broken wire inside
the insulation.

D

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:
1. This test checks the ability of the PCM to command

the PCS.

2. This test checks the PCS and internal wiring harness

for incorrect resistance.

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–57

DTC P0748 Pressure Control Solenoid (PCS) (Force Motor) Circuit Electrical 

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”.
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

2

1. 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 6

Go to Step 3

3

1. 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 5

Go to Step 4

4

Replace the PCS.

Is the replacement complete?

Go to Step 9

—

5

Repair the internal wiring harness for an open.

Is the repair complete?

Go to Step 9

—

6

Inspect/repair circuits J3–E4, M6–2(B),  J3–E3, and M6–1(E).

Was a problem found?

Go to Step 9

Go to Step 7

7

Inspect/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 9

Go to Step 8

8

Replace the PCM. Refer to Powertrain Control Module (PCM) in
Automatic Transmission (4L30–E) section.

Is the replacement complete?

Go to Step 9

—

9

1. 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