relay OPEL FRONTERA 1998 Repair Manual
Page 1202 of 6000
6E–85 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test
D06RW101
Circuit Description
When the ignition switch is first turned “ON,” the
powertrain  control  module  (PCM)  energizes  the  fuel
pump relay which applies power to the in-tank fuel pump.
The  fuel  pump  relay  will  remain  “ON”  as  long  as  the
engine  is  running or  cranking  and  the PCM is  receiving
58X  crankshaft  position  pulses.    If  no  58X  crankshaft
position  pulses  are  present,  the  PCM  de-energizes  the
fuel  pump  relay  within  2  seconds  after  the  ignition  is
turned “ON” or the engine is stopped.
The fuel pump delivers fuel to the fuel rail and injectors,
then  to  the  fuel  pressure  regulator.    The  fuel  pressure
regulator controls fuel pressure by allowing excess fuel to
be returned to the fuel tank.  With the engine stopped and
ignition “ON,” the fuel pump can be turned “ON” by using a
command by Tech 2.
Diagnostic Aids
An  intermittent  may  be  caused  by  a  poor  connection,
rubbed-through  wire  insulation,  or  a  wire  broken  inside
the insulation.  Check for the following items:
Poor  connection  or  damaged  harness  –  Inspect  the
PCM  harness  and  connectors  for  improper  mating,
broken  locks,  improperly  formed  or  damaged
terminals,  poor  terminal-to-wire  connection,  and
damaged harness.
Test Description
Number(s)  below  refer  to  the  step  number(s)  on  the
Diagnostic Chart.
2. If the fuel pump is operating but incorrect pressure is
noted, the fuel pump wiring is OK and the “Fuel
System Pressure Test” chart should be used for
diagnosis. 
Page 1203 of 6000
6E–86
ENGINE DRIVEABILITY AND EMISSIONS
CAUTION: To  reduce  the  risk  of  fire  and  personal
injury:
It  is  necessary  to  relieve  fuel  system  pressure
before connecting a fuel pressure gauge.  Refer to
Fuel Pressure Relief Procedure, below.
A  small  amount  of  fuel  may  be  released  when
disconnecting  the  fuel  lines.    Cover  fuel  line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out.  Place the towel in
an  approved  container  when  the  disconnect  is
completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Remove  the  fuel  pump  relay  from  the  underhood
relay center.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Gauge Installation
1. Remove the shoulder fitting cap.
2. Install fuel gauge 5-8840-0378-0 to the fuel feed line
located in front of and above the right side valve train
cover .
3. Reinstall the fuel pump relay.
Fuel System Electrical Test
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Read the “Caution” above.
2. Relieve the fuel system pressure and install the fuel
pump pressure gauge to the test fitting.
3. Use Tech 2 to command the fuel pump “ON.”
Is  there  an  immediate  pressure  build-up  which
indicates the pump is running?
—Go to Step 3Go to Step 4
31. Verify that the pump is not running by removing the
fuel filler cap and listening.
2. Command the pump “ON” with Tech 2.
Did the pump turn “OFF” after 2 seconds?
—
Te s t
completed
Go to Step 12
41. Ignition “OFF.”
2. Remove the fuel pump relay.
3. Using  a  test  light  connected  to  ground,  probe  the
battery feed to the relay.
Did the light illuminate?
—Go to Step 6Go to Step 5
5Repair short or open battery feed to fuel pump relay.
Is the action complete?
—Verify repair—
61. Connect  a  test  light  between  the  two  wires  that
connect to the fuel pump relay pull-in coil.
2. Ignition “ON.”
Did the test light illuminate for 2 seconds and then turn
off?
—Go to Step 12Go to Step 7
71. With a test light connected to battery (–), probe the
fuel  pump  relay  connector  at  the  wire  which  runs
from the relay pull-in coil to the PCM.
2. Ignition “ON.”
Did the test light illuminate for 2 seconds and then turn
off?
—Go to Step 8Go to Step 9
8Locate and repair open in the fuel pump relay ground
circuit.
Is the action complete?
—Verify repair— 
Page 1204 of 6000
6E–87 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test
StepNo Ye s Va l u e ( s ) Action
9Check for short or open between the PCM and the fuel
pump relay.
Was a problem found?
—Verify repairGo to Step 10
101. Check the fuel pump relay circuit for a poor terminal
connection at the PCM.
2. If a problem is found, replace terminal as necessary.
Was a problem found?
—Verify repairGo to Step 11
11Replace the PCM.
IMPORTANT:The  replacement  PCM  must  be
programmed.  Refer to 
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair—
121. Reconnect the fuel pump relay.
2. Disconnect the fuel pump electrical connector at the
fuel tank.
3. Using  a  test  light  connected  to  ground,  probe  the
fuel pump feed wire (harness side).
4. Command the fuel pump “ON” with Tech 2.
Did the light illuminate for 2 seconds?
—Go to Step 15Go to Step 13
131. Honk  the  horn  to  verify  that  the  horn  relay  is
functioning.
2. Substitute the horn relay for the fuel pump relay.
3. Leave the test light connected as in step 12.
4. Command the fuel pump “ON” with Tech 2.
Did the test light illuminate for 2 seconds when the fuel
pump was commanded “ON?”
—Go to Step 17Go to Step 14
141. Re-connect the horn relay in its proper location.
2. Check for a short circuit, blown fuse or open circuit
between the relay and the fuel tank.
Is the action complete?
—Verify repair—
151. With the fuel pump electrical connector at the fuel
tank disconnected, connect a test light between the
feed wire and the ground wire (harness side).
2. Command the fuel pump “ON” with Tech 2.
Did the test light illuminate for 2 seconds?
—Go to Step 18Go to Step 16
16Repair the open circuit in the fuel pump ground wire.
Is the action complete?
—Verify repair—
171. Re-connect the horn relay in its proper location.
2. Replace the fuel pump relay.
Is the action complete?
—Verify repair—
18Replace the fuel pump.
Is the action complete?
—Verify repair— 
Page 1206 of 6000
6E–89 ENGINE DRIVEABILITY AND EMISSIONS
The  valve  or  valve  seat  within  the  fuel  pressure
regulator.
The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire.  A lean condition can be diagnosed using
a Tech II Tech 2.  If an extremely lean condition
occurs, the oxygen sensor(s) will stop toggling.  The
oxygen sensor output voltage(s) will drop below 500
mV.  Also, the fuel injector pulse width will increase.
IMPORTANT:Make  sure  the  fuel  system  is  not
operating in the “Fuel Cut-Off Mode.”
When the engine is at idle, the manifold pressure is
low (high vacuum).  This low pressure (high vacuum)
is  applied  to  the  fuel  pressure  regulator  diaphragm.
The  low  pressure  (high vacuum)  will  offset  the
pressure being applied to the fuel pressure regulator
diaphragm  by  the  spring  inside  the  fuel  pressure
regulator.  When this happens, the result is lower fuel
pressure.  The fuel pressure at idle will vary slightly as
the  barometric  pressure  changes,  but  the  fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine “OFF.”
16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking.  If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:
Remove  the  fuel  rail,  but  leave  the  fuel  lines  and
injectors connected to the fuel rail.  Refer to
 Fuel Rail
Assembly 
in On-Vehicle Service.
Lift the fuel rail just enough to leave the fuel injector
nozzles in the fuel injector ports.
CAUTION: In  order  to  reduce  the  risk  of  fire  and
personal injury that may result from fuel spraying on
the engine, verify that the fuel rail is positioned over
the fuel injector ports and verify  that the fuel injector
retaining clips are intact.
Pressurize the fuel system by connecting a 10 amp
fused jumper between B+ and the fuel pump relay
connector.
Visually  and  physically  inspect  the  fuel  injector
nozzles for leaks.
17.A rich condition may result from the fuel pressure
being above 376 kPa (55 psi).  A rich condition may
cause a DTC P0132 or a DTC P0172 to set.
Driveability conditions associated with rich
conditions can include hard starting (followed by
black smoke) and a strong sulfur smell in the
exhaust.20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure
below 333 kPa (48 psi).  A lean condition may
cause a DTC P0131 or a DTC P0171 to set.
Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold ), hesitation, poor driveability, lack of
power, surging , and misfiring.
22.Restricting the fuel return line causes  the fuel
pressure to rise above the regulated fuel pressure.
Command the fuel pump “ON” with Tech 2.  The fuel
pressure should rise above 376 kPa (55 psi) as the
fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414 kPa
( 6 0 p s i ) .   F u e l  p r e s s u r e  i n  e x c e s s  o f  4 1 4 k P a  ( 6 0 p s i )  m a y
damage the fuel pressure regulator.
CAUTION: To  reduce  the  risk  of  fire  and  personal
injury:
It  is  necessary  to  relieve  fuel  system  pressure
before connecting a fuel pressure gauge.  Refer to
Fuel Pressure Relief Procedure, below.
A  small  amount  of  fuel  may  be  released  when
disconnecting  the  fuel  lines.    Cover  fuel  line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out.  Place the towel in
an  approved  container  when  the  disconnect  is
completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Remove  the  fuel  pump  relay  from  the  underhood
relay center.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Gauge Installation
1. Remove the shoulder fitting cap.
2. Install fuel gauge 5-8840-0378-0 to the fuel feed line
located in front of and above the right side valve train
cover.
3. Reinstall the fuel pump relay. 
Page 1228 of 6000
6E–111 ENGINE DRIVEABILITY AND EMISSIONS
DTC P0103 – MAF Sensor Circuit High Frequency
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Ignition “ON,” engine “OFF.”
2. Review and record Tech 2 Failure Records data.
3. Operate  the  vehicle  within  Failure  Records
conditions as noted.
4. Using a Tech 2, monitor “DTC” info for DTC P0103.
Does  the  Tech  2  indicate  DTC  P0103  failed  this
ignition?
—Go to Step 3
Refer to
Diagnostic
Aids
31. Start the engine.
2. With  the  engine  idling,  monitor  “MAF  Frequency”
display on the Tech 2.
Is “MAF Frequency” above the specified value?
219 g/SecGo to Step 4Go to Step 7
41. Ignition “OFF.”
2. Disconnect the MAF sensor connector.
3. Ignition “ON,” engine idling.
4. Using a Tech 2, monitor “MAF Frequency.”
Does  the  Tech  2  indicate  a  “MAF  Frequency”  at  the
specified value?
0.0 g/SecGo to Step 5Go to Step 6
5Replace the MAF sensor.
Is the action complete?
—Verify repairGo to Step 8
61. Check the MAF harness for incorrect routing near
high  voltage  components  (solenoids,  relays,
motors).
2. If  incorrect  routing  is  found,    correct  the  harness
routing.
Was a problem found?
—Verify repairGo to Step 7
71. With  the  engine  idling,  monitor  “MAF  Frequency”
display on the Tech 2.
2. Quickly  snap  open  throttle  to  wide  open  throttle
while under a road load and record value.
Does the Tech 2 indicate “MAF Frequency” above the
specified value?
219 g/SecGo to Step 5Go to Step 8
8Replace the PCM.
IMPORTANT:The  replacement  PCM  must  be
programmed.  Refer to 
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?—Verify repair— 
Page 1363 of 6000
6E–246
ENGINE DRIVEABILITY AND EMISSIONS
amounts of fuel at idle, but may not be able to supply
enough fuel during heavy acceleration.
Water  or  alcohol  in  the  fuel  may  cause  low  HO2S
voltage during acceleration.
Check for faulty or plugged fuel injector(s).
Check for low fuel.
Test Description
Number(s)  below  refer  to the  step  number(s)  on  the
Diagnostic Chart.4. When the engine is idling or at steady cruise, the
HO2S voltage should vary from between
approximately 100 mV to 900 mV.  It is possible to
measure a satisfactory fuel pressure at idle even
though the pressure may drop at high flow
requirements.  It may be necessary to watch fuel
pressure at high engine load.
5. Wrap a shop towel around the fuel pressure
connector to absorb any small amount of fuel
leakage that may occur when installing gauge.
Ignition “ON,” pump pressure should be 280-320
kPa.
DTC P1171 – Fuel System Lean During Acceleration
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Are any component-related DTCs set?
—
Go to
component
DTC charts
Go to Step 3
31. Check  the  vehicle’s  fuel  tank  for  an  adequate
amount of fuel.
2. Add fuel to the vehicle’s fuel tank if the tank is almost
empty.
Was fuel added to the vehicle’s fuel tank?
—Go to Step 4Go to Step 5
41. Place the transmission in park.
2. Using  Tech  2,  observe  HO2S  1  voltage  while
running warm engine 75
C-95C (167F-203F) at
1200 RPM.
3. HO2S  1  voltage  should  vary  within  the  specified
range.
4. Quickly open the throttle halfway for a few seconds.
Did the voltage suddenly rise toward the high end of the
specified range?
100-900 mV
Go to Chart
A-7
Go to Step 5
51. Disconnect  the  fuel  pump  relay  and  crank  the
engine to relieve the fuel pressure.
2. Install the fuel pressure gauge.
3. Start  the  engine  and  idle  at  normal  operating
temperature.
4. Disconnect  the  vacuum  line  going  to  the  fuel
pressure regulator.
With the engine running, is the fuel pressure within the
specified range?
280-325 kPa
(41-46 psi)
Go to OBD
System
Check
Go to Step 6
6Check for restricted fuel lines or restricted in-line filter.
Was a problem found?
—Verify repairGo to Step 7 
Page 1364 of 6000
6E–247 ENGINE DRIVEABILITY AND EMISSIONS
DTC P1171 – Fuel System Lean During Acceleration
StepNo Ye s Va l u e ( s ) Action
71. Ignition “OFF.”
2. Remove  the  fuel  pump  relay  and  replace  it  with  a
fused jumper which will connect the relay’s battery
terminal  to  the  terminal  leading  to  the  fuel  pump
fuse.
3. While the fuel pump is operating, use pliers to slowly
close  the  return  line  (do  not  exceed  the  first
specified value).
Using the pliers to restrict the return line, can the fuel
pressure  be  manipulated  to  exceed  the  second
specified value?
414 kPa
(60 psi)
325 kPa
(46 psi)
Go to
Diagnostic
Aids
Go to Step 8
8Check for:
Faulty fuel pump
Restricted fuel pump strainer (sock)
Incorrect fuel pump
Incorrect fuel being used
Hot fuel
Is the action complete?
—Verify repair— 
Page 1376 of 6000
6E–259 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1640 Driver-1-Input High Voltage
Circuit Description
Output  driver  modules  (ODMs)  are  used  by  the
powertrain  control  module  (PCM)  to  turn  “ON”  many  of
the  current-driven  devices  that  are  needed  to  control
various engine and transmission functions.  Each ODM is
capable  of  controlling  up  to  7  separate  outputs  by
applying  ground  to  the  device  which  the  PCM  is
commanding “ON.”
Unlike  the  Quad  Driver  Modules  (QDMs)  used  in  prior
model  years,  ODMs  have  the  capability  of  diagnosing
each output circuit individually.  DTC P1640 set indicates
an improper voltage level has been detected on an ODM
output.
Since  A/C  is  an  option,  No  A/C  will  cause  the  air
conditioning clutch relay output to always fault.  If a fault is
seen on the air conditioning clutch relay output, it will not
be logged as a fault until the A/C request input interrupts a
high voltage, indicating that A/C has been installed.
Conditions for Setting the DTC
Ignition “ON.”
Engine running.
No DTC 1618.
Ignition voltage is above 13.2 volts for 4 seconds.
Output  voltage  does  not  equal  ignition  voltage  when
output is “OFF” or output voltage is not less than 1 volt
when output is “ON.”
Above conditions occur for at least 1 second.
Action Taken When the DTC Sets
The  PCM  will  not  illuminate  the  malfunction  indicator
lamp (MIL).
The  PCM  will  store  conditions  which  were  present
when the DTC was set as Failure Records only.  This
information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC
DTC P1640 can be cleared by using the Tech 2 “Clear
Info”  function  or  by  disconnecting  the  PCM  battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at PCM – Inspect harness connectors
for  backed-out  terminals,  improper  mating,  broken
locks,  improperly  formed  or  damaged  terminals,  and
poor terminal-to-wire connection.
Damaged  harness  –  Inspect  the  wiring  harness  for
damage,  If the harness appears to be OK, disconnect
the  PCM,  turn  the  ignition  “ON”  and  observe  a
voltmeter connected to the suspect driver circuit at the
PCM harness connector while moving connectors and
wiring  harnesses  relates  to  the  MIL.    A  change  in
voltage will indicate the location of the fault.
Poor  connection  at  component  –  Examine  for
damaged  connectors,  unplugged  connector,  or
damaged  terminals  at  the  following  locations:
Instrument  cluster  harness,  canister  purge  solenoid,
A/C clutch relay.  An open ignition feed circuit at any of
these components will cause DTC P1640 to be set.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs.  This
may assist in diagnosing the condition.
The  following  PCM  pins  are  controlled  by  output  driver
modules (ODMs):
A13 – “Check Engine Lamp”
A14 – SVS (”Check Trans”)
B14 – A/C Clutch
Test Description
Number(s)  below  refer  to  the  step  number(s)  on  the
Diagnostic Chart.
6. The Tech 2 Driver Module Status indicates the PCM
pin that is affected.
11. The Tech 2 may indicate “short circuit” even when
the problem is an open circuit.  The cause of an
open circuit may be in the component itself-lamp,
purge, solenoid, or A/C compressor relay.
13.A short to ground on the ignition side of the
component will blow the fuse.  Since the fuse was
checked in Step 4, a short to ground would be
between the affected component and the PCM. 
Page 1432 of 6000
6E–315 ENGINE DRIVEABILITY AND EMISSIONS
Installation Procedure
1. Install the O-ring backup on the fuel injector.
2. Install the new O-ring on the fuel injector.
3. Install the fuel injector on the fuel rail.
055RW009
4. Use new fuel injector retainer clips to retain the fuel
injector to the fuel rail.
5. Coat the end of the fuel injector with engine oil.
6. Install the fuel rail.  Refer to 
Fuel Rail.
014RW164
7. Install the upper intake manifold.  Refer to Common
Chamber in Engine Mechanical.
8. Install the engine cover.
9. Connect the negative battery cable.
Fuel Pressure Regulator
Removal Procedure
CAUTION: To  reduce  the  risk  of  fire  and  personal
injury,  it  is  necessary  to  relieve  the  fuel  system
pressure  before  servicing  the  fuel  system
components.
CAUTION: After  relieving  the  system  pressure,  a
small amount of fuel may be released when servicing
fuel  lines  or  connections.    Reduce  the  chance  of
personal injury by covering the fuel line fittings with
a shop towel before disconnecting the fittings.  The
towels will absorb any fuel that may leak out.  When
the  disconnect  is  completed,  place  the  towel  in  an
approved container.
NOTE: Compressed  air  must  never  be  used  to  test  or
clean  a  fuel  pressure  regulator,  as  damage  to  the  fuel
pressure regulator may result.
NOTE: To prevent damage to the fuel pressure regulator,
do not immerse the pressure regulator in solvent.
1. Depressurize the fuel system.  Refer to 
Fuel Pressure
Relief Procedure
.
2. Disconnect the negative battery cable.
3. Remove  the  fuel  pump  relay.    Refer  to 
Fuel  Pump
Relay
.
4. Remove  the  pressure  regulator  hose  from  the  fuel
pressure regulator.
014RW110 
Page 1434 of 6000
6E–317 ENGINE DRIVEABILITY AND EMISSIONS
Installation Procedure
1. Install the fuel pressure regulator attaching screw.
Tighten
Tighten the fuel pressure regulator attaching screw
to 3 Nꞏm (26 lb in.).
F06RW043
2. Install the fuel pressure regulator on the fuel rail.
3. Install the two bolts to the protector that secures the
common chamber.
014RW109
4. Install  the  pressure  regulator  hose  to  the  fuel
pressure regulator.
014RW110
5. Install the fuel pump relay.  Refer to Fuel Pump Relay.
6. Connect the negative battery cable.
7. Crank the engine until it starts.  Cranking the engine
may take longer than usual due to trapped air in the
fuel lines.
Fuel Metering System
Fuel Pressure Relief Procedure
CAUTION: To  reduce  the  risk  of  fire  and  personal
injury,  it  is  necessary  to  relieve  the  fuel  system
pressure  before  servicing  the  fuel  system
components.
CAUTION: After  relieving  the  system  pressure,  a
small amount of fuel may be released when servicing
fuel  lines  or  connections.    Reduce  the  chance  of
personal injury by covering the fuel line fittings with
a shop towel before you disconnect the fittings.  The
towels will absorb any fuel that may leak out.  When
the  disconnect  is  completed,  place  the  towel  in  an
approved container.
1. Remove the fuel cap.