lights OPEL FRONTERA 1998 Owner's Guide

6E–176
4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Symptom Diagnosis
Preliminary Checks
Before using this section, perform the “On–Board
Diagnostic (OBD) System Check” and verify all of the
following items:
The powertrain control module (ECM) and
malfunction indicator lamp (MIL) (CHECK ENGINE
lamp) are operating correctly.
There are no DTC(s) stored.
Tech–2 data is within normal operating range. Refer
to
Typical Scan Data Values.
Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
Visual/Physical Check
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time.
This check should include the following items:
ECM grounds for cleanliness, tightness and proper
location.
Vacuum hoses for splits, kinks, and proper
connections, as shown on the “Vehicle Emission
Control Information” label. Check thoroughly for any
type of leak or restriction.
Air intake ducts for collapsed or damaged areas.
Injector wires for cracking, hardness, and carbon
tracking.
Wiring for proper connections, pinches and cuts.
Intermittents
IMPORTANT:An intermittent problem may or may not
turn on the malfunction indicator lamp (MIL) or store a
DTC. DO NOT use the Diagnostic Trouble Code (DTC)
charts for intermittent problems. The fault must be
present to locate the problem.
Most intermittent problems are caused by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions:
Poor mating of the connector halves or a terminal not
fully seated in the connector (backed out).
Improperly formed or damaged terminal.
All connector terminals in the problem circuit should
be carefully checked for proper contact tension.
Poor terminal–to–wire connection. This requires
removing the terminal from the connector body to
check.
Road test the vehicle with a Digital Multimeter
(5-8840-0285-0) connected to a suspected circuit. An
abnormal voltage when the malfunction occurs is a good
indication that there is a fault in the circuit being
monitored.
Use a scan tool to help detect intermittent conditions. The
scan tools have several features that can be used to
locate an intermittent condition. Use the following feature
to find intermittent faults:
Using a Tech–2 “Freeze Frame” buffer or “Failure
Records” buffer can aid in locating an intermittent
condition. Review and record the information in the
freeze frame or failure record associated with the
intermittent DTC being diagnosed. The vehicle can
be driven within the conditions that were present
when the DTC originally set.
To check for loss of diagnostic code memory, disconnect
the MAP sensor and idle the engine until the MIL (CHECK
ENGINE lamp) comes on. DTC P0107 should be stored
and kept in memory when the ignition is turned “OFF.” If
not, the ECM is faulty. When this test is completed, make
sure that you clear the DTC P0107 from memory.
An intermittent MIL (CHECK ENGINE lamp) with no
stored DTC may be caused by the following:
MIL (CHECK ENGINE lamp) wire to ECM shorted to
ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Check for improper installation of electrical options such
as lights, cellular phones, etc.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in
Electrical Diagnosis).
If problem has not been found, refer to
ECM Connector
Symptom
tables.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–9
MAJOR INPUT/OUTPUT COMPONENTS
Component Function
Input
Vehicle speed sensor (Speedometer) Detects the vehicle speed (Back-up sensor of output
revolution sensor).
Output revolution sensor (Transmission) Detects the vehicle speed.
Input revolution sensor (Transmission) Detects the input revolution (O/D direct clutch drum
revolution).
Engine revolution sensor Detects the engine revolution.
Throttle position sensor Detects the throttle opening rate.
Neutral start switch Detects the select lever position.
Pattern select switch Detects whether the driver has selected "NORMAL",
"POWER", or "WINTER" mode.
Overdrive off switch Detects whether the driver has selected O/D.
Brake lamp switch Detects whether the driver has pressed the brake pedal or
not.
Oil temperature sensor Detects the oil temperature.
Diagnostic star t switch Star ts self-diagnosis and displays a code for faulty part if
any.
Input/Output
Data link connector When connected with Tech2 or tester, can communicate
the data for function check, etc.
Output
Shift solenoid S1, S2 Selects shift point and gear position suited to the vehicle
running condition on the basis of TCM output.
Lock-up control solenoid SL Control the lock-up clutch suited to the vehicle running
condition on the basis of TCM output.
Pressure control solenoid STH Adjusts throttle pressure by energizing current of linear
pressure control solenoid to prevent the shift shock and to
obtain shift smoothly.
"CHECK TRANS" lamp When trouble has occurred to throttle position sensor,
vehicle speed sensor, or solenoid, "CHECK TRANS" lamp
is blinked to warn the driver. If also displays the trouble
code.
A/T OIL TEMP warning lamp Lights when ATF oil temperature rises. (Turned on at
greater than 146
C . Turned off at less than 126C.
Power mode lamp Informs the driver whether the vehicle is in power mode or
not.
Winter mode lamp Informs the driver whether the vehicle is in winter mode or
not.
Computer
Transmission Control Module (TCM) Based on the signal from each switch and sensors, judges
necessary shift point and lock-up operation, and send
signal to each solenoid.

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–23
INTERMITTENT CONDITIONS
If the Tech2 displays a code as intermittent, or if after a
test drive a code does not reappear, the problem is most
likely a faulty electrical connection or loose wiring.
Terminals should always be the prime suspect.
Intermittent rarely occur in sophisticated electronic
components such as the Transmission Control Module
(TCM).
When an intermittent problem is encountered, check
suspect circuits for:
• Poor terminal to wire connection.
• Terminals not fully seated in the connector body
(backed out).
• Improperly formed or damaged terminals.
• Loose, dirty, or corroded ground connections.
HINT: Any time you have an intermittent in more than
one circuit, check whether the circuits share a
common ground connection.
• Pinched or damaged wires.
• Electro-Magnetic Interference (EMI)
HINT: Check that all wires are properly routed away
from spark plug wires, distributor wires, coil,
and generator. Also check for improperly
installed electrical options, such as lights, 2-
way radios, etc.
Use the F2: SNAPSHOT mode of the Tech2 to help
isolate the cause of an intermittent fault. The snapshot
mode will record information before and after the
problem occurs. Set the snapshot to "trigger" on the
suspect code (or codes) or, if you notice the repor ted
symptom during test drive, trigger the snapshot
manually.
After the snapshot has been triggered, command the
Tech2 to play back the flow of data recorded from each
of the various sensors. Signs of an intermittent fault in a
sensor circuit are a sudden unexplainable jump in data
values out of the normal range.