Opel Frontera UBS. Manual - part 1361

6E–38

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

On- Board Diagnostic (OBD) System Check

 

Step

Action

Value(s)

Yes

No

1

1. Ignition “ON,” engine “OFF.”
2. Observe the malfunction indicator lamp (MIL or

“Check Engine” lamp). 

Is the MIL (“Check Engine” lamp)“ON?”

—

Go to 

Step 2

Go to 

No MIL

(“Check

Engine” lamp)

2

1. Ignition “OFF.”
2. Install a Tech 2.
3. Ignition “ON.”
4. Attempt to display ECM engine data with the Tech 2.

Does the Tech 2 display ECM data?

—

Go to 

Step 3

Go to 

Step 8

3

1. Using the Tech 2 output tests function, select MIL

(“Check Engine” lamp) dash lamp control and
command the MIL (“Check Engine” lamp) “OFF.”

2. Observe the MIL (“Check Engine” lamp).

Did the MIL (“Check Engine” lamp) turn “OFF?”

—

Go to 

Step 4

Go to 

MIL

(“Check

Engine” lamp)

On Steady

4

Attempt to start the engine.

Did the engine start and continue to run?

—

Go to 

Step 5

Go to 

Cranks

But Will Not

Run

5

Select “Display DTCs” with the Tech 2.

Are any DTCs stored?

—

Go to 

Step 6

Go to 

Step 7

6

Are two or more of the following DTCs stored?
 A Group; P0337, P0342, P1193, P1404, P1405,
P1488
 B Group; P0337, P0342
 C Group; P0112, P0117, P0182, P0197
 D Group; P0107, P0405, P1194, P1485

—

Go to 

Chart,

“Multiple

ECM

Information

Sensor DTCs

Set”

Go to

applicable
DTC table

7

Compare ECM data values displayed on the Tech 2 to
the typical engine scan data values.

Are the displayed values normal or close to the typical
values?

—

Go to 

Step 8

Refer to

indicated

Component

System
Checks

8

1. Ignition “OFF,” disconnect the ECM.
2. Ignition “ON,” engine “OFF.”
3. Check the Class 2 data circuit for an open, short  to

ground, or short to voltage.  Also, check the DLC
ignition feed circuit for an open or short to ground
and the DLC ground circuit for an open.

4. If a problem is found, repair as necessary.

Was a problem found?

—

Go to 

Step 2

Go to 

Step 9

9

Check the Tech 2 on other vehicle.

Was Tech 2 abnormal?

—

Go to 

Step 11

Go to 

Step 10

10

Replace the ECM (Refer to the Data Programming in
Case of ECM change).

Is the action complete?

—

Go to 

Step 2

—

11

Repair the Tech 2 or prepare another Tech 2.

Is the action complete?

—

Go to 

Step 2

—

6E–39

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

Engine Control Module ECM

Diagnosis

To read and clear diagnostic trouble codes, use a Tech 2.
IMPORTANT:

Use of a Tech 2 is recommended to clear

diagnostic trouble codes from the ECM memory.
Diagnostic trouble codes can also be cleared by turning
the ignition “OFF” and disconnecting the battery power
from the ECM for 30 seconds.  Turning off the ignition and
disconnecting the battery power from the ECM will cause
all diagnostic information in the ECM memory to be
cleared.  Therefore, all the diagnostic tests will have to be
re-run.
Since the ECM can have a failure which may affect only
one circuit, following the diagnostic procedures in this
section will determine which circuit has a problem and
where it is.
If a diagnostic chart indicates that the ECM connections
or the ECM is the cause of a problem, and the ECM is
replaced, but this does not correct the problem, one of the
following may be the reason:

D

There is a problem with the ECM terminal
connections.  The terminals may have to be removed
from the connector in order to check them properly.

D

The problem is intermittent.  This means that the
problem is not present at the time the system is being
checked.  In this case, refer to the 

Symptoms portion

of the manual and make a careful physical inspection
of  all components and wiring associated with the
affected system.

D

There is a shorted solenoid, relay coil, or harness.
Solenoids and relays are turned “ON” and “OFF” by
the ECM using internal electronic switches called
drivers.  A shorted solenoid, relay coil, or harness will
not damage the ECM but will cause the solenoid or
relay to be inoperative.

Multiple ECM Information Sensor

DTCS Set

Circuit Description

The Engine Control Module ECM monitors various
sensors to determine the engine operating conditions.
The ECM controls fuel delivery, spark advance,
transmission operation, and emission control device
operation based on the sensor inputs.
The ECM provides a sensor ground to all of the sensors.
The ECM applies 5 volts through a pull-up resistor, and
determines the status of the following sensors by
monitoring the voltage present between the 5-volt supply
and the resistor:

D

The fuel temperature (FT) sensor

D

The engine coolant temperature (ECT) sensor

D

The Intake air temperature (IAT) sensor

The ECM provides the following sensors with a 5-volt
reference and a sensor ground signal:

D

The Intake throttle position sensor

D

The manifold absolute pressure sensor

D

The rail pressure sensor

D

The accelerator position sensor

D

The oil temperature sensor

D

The camshaft position sensor

D

The crankshaft position sensor

D

The EGR pressure sensor

The ECM monitors the signals from these sensors in
order to determine their operating status.

Diagnostic Aids

IMPORTANT:

Be sure to inspect ECM and engine

grounds for being secure and clean.
A short to voltage in one of the sensor input circuits may
cause one or more of the following DTCs to be set:

D

P0337

D

P0342

D

P1193

D

P1404

D

P1405

D

P1488

IMPORTANT:

If a sensor input circuit has been shorted

to voltage, ensure that the sensor is not damaged. A
damaged sensor will continue to indicate a high or low
voltage after the affected circuit has been repaired.  If the
sensor has been damaged, replace it.
An open in the sensor ground circuit between the ECM
and the splice will cause one or more of the following
DTCs to be set:

D

P0337

D

P0342

D

P0117

A short to ground in the 5-volt reference A or B circuit will
cause one or more of the following DTCs to be set:

D

P0112

D

P0117

D

P0182

D

P0197

An open in the 5-volt reference circuit A, between the
ECM and the splice will cause one or more of the following
DTCs to be set:

D

P0107

D

P0405

D

P1194

D

P0122

An open in the 5-volt reference circuit B, between the
ECM and the splice will cause one or more of the following
DTCs to be set:

D

P1485

Check for the following conditions:

D

Poor connection at ECM. Inspect the harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damage
terminals, and a poor terminal-to-wire connection.

D

Damaged harness. Inspect the wiring harness for
damage.  If the harness is not damaged, observe an
affected sensor’s displayed value on the Tech 2 with
the ignition “ON” and the engine “OFF” while you
move the connectors and the wiring harnesses
related to the following sensors:

D

ECT Sensor

6E–40

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

D

MAP Sensor

D

CMP Sensor

D

CKP Sensor

D

EGR Pressure Sensor

D

EGR VSV 

D

RPCV

D

IAT Sensor

D

Intake Throttle Motor

D

Fuel Temperature Sensor

D

Oil Temperature Sensor

D

Rail Pressure Sensor

Multiple ECM Information Sensor DTCs Set

 

Step

Action

Value(s)

Yes

No

1

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Turn the ignition “OFF,” disconnect the ECM.
2. Turn the ignition “ON,” check the 5 volt reference D

circuit for the following conditions:

D

D poor connection at the ECM.

D

An open between the ECM connector and the
splice.

D

D short to ground.

D

D short to voltage.

Is there an open or short?

—

Go to 

Step 3

Go to 

Step 4

3

Repair the open or short.

Is the action complete?

—

Verify repair

—

4

Check the sensor ground circuit for the following
conditions:

D

A poor connection at the ECM or the affected
sensors.

D

An open between the ECM connector and the
affected sensors.

Is there an open or a poor connection?

—

Go to 

Step 5

Go to 

Step 6

5

Repair the open or the poor connection.

Is the action complete?

—

Verify repair

Go to 

Step 6

6

Replace the ECM (Refer to the Data Programming in
Case of ECM change).

Is the action complete?

—

Go to 

OBD

System

Check

—

6E–41

4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS

EGR (Exhaust Gas Recirculation)

Diagnosis

D

A diagnosis of the EGR system is covered by DTC
P1403.

D

EGR VSV circuit diagnosis is covered by DTC P1404.

D

EGR pressure sensor diagnosis is covered by DTC
P405 and/or P406.

D

EGR EVRV circuit diagnosis is covered by DTC
P1405. Refer to the DTC charts.

Tech 2 Data Definitions and Ranges

A/C CLUTCH–Tech 2 Displays ON or OFF–
Indicates whether the A/C has commanded the A/C
clutch ON.

MAP kPa — Tech 2 Range 10-105 kPa/0.00-5.00
Volts —
The manifold absolute pressure reading is determined
from the MAP sensor signal monitored during key up and
wide open throttle (WOT) conditions.  The manifold
absolute pressure is used to compensate for altitude
differences and is normally displayed around “61-104”
depending on altitude and manifold absolute pressure.

CMP ACT. COUNTER –Cam Position

DESIRED IDLE — Tech 2 Range 0-3187 RPM —
The idle speed that the ECM is commanding.  The ECM
will compensate for various engine loads based on engine
coolant temperature,  to keep the engine at the desired
speed.

ECT — (Engine Coolant Temperature) Tech 2
Range –40

°

C to 151

°

C (–40

°

F to 304

°

F) —

The engine coolant temperature (ECT) is mounted in the
coolant stream and sends engine temperature
information to the ECM.  The ECM applies 5 volts to the
ECT sensor circuit.  The sensor is a thermistor which
changes internal resistance as temperature changes.
When the sensor is cold (high resistance), the ECM
monitors a high signal voltage and interprets that as a cold
engine.  As the sensor warms (decreasing resistance),
the voltage signal will decrease and the ECM will interpret
the lower voltage as a warm engine.

ENGINE RUN TIME — Tech 2 Range
00:00:00-99:99:99 Hrs:Min:Sec —
Indicates the time elapsed since the engine was started.
If the engine is stopped, engine run time will be reset to
00:00:00.

ENGINE SPEED — Range 0-9999 RPM —
Engine speed is computed by the ECM from the 57X
reference input.  It should remain close to desired idle
under various engine loads with engine idling.

Air Intake Valve meter POSITION — Tech 2 Range
0-100 % —

IAT (INTAKE AIR TEMPERATURE)— Tech 2 Range
–40

°

C to 151

°

C (–40

°

F to 304

°

F) —

The ECM converts the resistance of the intake air
temperature sensor to degrees.  Intake air temperature
(IAT) is used by the ECM to adjust fuel delivery and spark
timing according to incoming air density.

MAP — Tech 2 Range 10-105 kPa (0.00-4.97 Volts)—
The manifold absolute pressure (MAP) sensor measures
the change in the boost pressure.

MIL — Tech 2 Displays ON or OFF —
Indicates the ECM commanded state of the malfunction
indicator lamp.

AP — Tech 2 Range 0%-100% —
AP (Accelerator position)  angle is computed by the ECM
from the AP sensor voltage.  AP angle should display
“0%” at idle and “100%” at wide open throttle.

AP SENSOR — Tech 2 Range 0.00-5.00 Volts —
The voltage being monitored by the ECM on the AP
sensor signal circuit.

VEHICLE SPEED—Tech 2 Range 0-255 km/h (0-155
mph)–
The vehicle speed sensor signal is converted into km/h
and mph for display.

Typical Scan Data Values

Use the Typical Scan Data Values Table only after the
On-Board Diagnostic System Check has been
completed, no DTC(s) were noted, and you have
determined that the on-board diagnostics are functioning
properly.  Tech 2 values from a properly-running engine
may be used for comparison with the engine you are
diagnosing.  The typical scan data values represent
values that would be seen on a normally-running engine.

NOTE: A Tech 2 that displays faulty data should not be
used, and the problem should be reported to the Tech 2
manufacturer.  Use of a faulty Tech 2 can result in
misdiagnosis and unnecessary replacement of parts.

Only the parameters listed below are referred to in this
service manual for use in diagnosis.  For further
information on using the Tech 2 to diagnose the ECM and
related sensors, refer to the applicable reference section
listed below.  If all values are within the typical range
described below, refer to the 

Symptoms section for

diagnosis.

Test Conditions

Engine running, lower radiator hose hot, transmission in
park or neutral, accessaries off, brake not applied and air
conditioning off.