2004 DAEWOO NUBIRA check engine

ENGINE CONTROLS 1F – 289
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1231
FUEL PUMP RELAY HIGH VOLTAGE (1.4L DOHC)
Circuit Description
When the ignition switch is turned ON, the ECM will acti-
vate the fuel pump relay and run the in–tank fuel pump.
The fuel pump will operate as long as the engine is crank-
ing or running and the ECM is receiving ignition reference
pulses.
Conditions for Setting the DTC
S This DTC can be stored in ”key–on” status.
S A high voltage condition exists.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
S The ECM will store conditions which were present
when the DTC was set as Failure Records data
only.
S This information will not be stored in the Freeze
Frame data.Conditions for Clearing the MIL/DTC
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions.
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminals to wire connection
S Physical damage to the wiring harness

1F – 290IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P1231 – Fuel Pump Relay High Voltage (1.4L DOHC)
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition switch to LOCK for 10 sec-
onds.
2. Turn the Turn the ignition switch to ON.
3. Listen for in–tank fuel pump operation.
Does the fuel pump operate?2.55 secondsGo to
”Diagnostic
Aids”Go to Step 3
3Check for short to battery voltage or low voltage in
the wire between the fuel pump relay connector ter-
minal 87 and fuel pump connector 3.
Is the problem found?–Go to Step 7Go to Step 5
41. Repair the wire between the fuel pump relay
connector terminal 87 and fuel pump connector
terminal 3.
2. Install the fuel pump relay.
3. Turn the engine OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsGo to Step 11–
51. Replace the fuel pump relay.
2. Turn the ignition OFF for 10 seconds.
3. Clear any DTCs from ECM.
4. Turn the Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsGo to Step 11Go to Step 6
6Check for short to battery voltage wire between the
fuel pump relay connector terminal 86 and the igni-
tion after key ON(IGN 1).
Is the problem found?–Go to Step 8Go to Step 7
7Check for an open wire between the fuel pump relay
connector terminal 85 and the ECM connector termi-
nal 6.
Is the problem found?–Go to Step 9Go to Step 10
81. Repair the wire between the fuel pump relay
connector terminal 86 and the ignition key ON
(IGN1).
2. Install the fuel pump relay.
3. Turn the ignition OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 10
91. Repair the wire between the fuel pump relay
connector terminal 85 and the ECM connector
terminal 6.
2. Install the fuel pump relay.
3. Turn the ignition OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 10

ENGINE CONTROLS 1F – 291
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
101. Replace the ECM.
2. Turn the ignition OFF for 10 seconds.
3. Clear any DTCs from ECM.
4. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 11
111. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC ad specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 12Go to Step 2
12Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

1F – 292IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1231
FUEL PUMP RELAY HIGH VOLTAGE (1.6L DOHC)
Circuit Description
When the ignition switch is turned ON, the ECM will acti-
vate the fuel pump relay and run the in–tank fuel pump.
The fuel pump will operate as long as the engine is crank-
ing or running and the ECM is receiving ignition reference
pulses.
Conditions for Setting the DTC
S This DTC can be stored in ”key–on” status.
S A high voltage condition exists.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illumi-
nate.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Freeze Frame and Records buffers.
S A history DTC is stored.
S Coolant fan turns ON.
Conditions for Clearing the MIL/DTCS The MIL will turn off after consecutive ignition
cycles in which the diagnostic runs without a fault.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for 10 sec-
onds.
Diagnostic Aids
An Intermittent problem may be caused by a poor connec-
tion, rubbed through wire insulation, or wire that is broken
inside the insulation.
Any circuitry, that is suspected as causing the complaint,
should be thoroughly checked for the following conditions.
S Backed–out terminals
S Improper mating
S Broken locks
S Improperly formed
S Damaged terminals
S Poor terminals to wire connection
S Physical damage to the wiring harness

ENGINE CONTROLS 1F – 293
DAEWOO V–121 BL4
DTC P1231 – Fuel Pump Relay High Voltage (1.6L DOHC)
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the system check complete?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition switch to LOCK for 10 sec-
onds.
2. Turn the Turn the ignition switch to ON.
3. Listen for in–tank fuel pump operation.
Does the fuel pump operate?2.55 secondsGo to
”Diagnostic
Aids”Go to Step 3
3Check for short to battery voltage or low voltage in
the wire between the fuel pump relay connector ter-
minal 87 and fuel pump connector 3.
Is the problem found?–Go to Step 7Go to Step 5
41. Repair the wire between the fuel pump relay
connector terminal 87 and fuel pump connector
terminal 3.
2. Install the fuel pump relay.
3. Turn the engine OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsGo to Step 11–
51. Replace the fuel pump relay.
2. Turn the ignition OFF for 10 seconds.
3. Clear any DTCs from ECM.
4. Turn the Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsGo to Step 11Go to Step 6
6Check for short to battery voltage wire between the
fuel pump relay connector terminal 86 and the igni-
tion after key ON(IGN 1).
Is the problem found?–Go to Step 8Go to Step 7
7Check for an open wire between the fuel pump relay
connector terminal 85 and the ECM connector termi-
nal 6.
Is the problem found?–Go to Step 9Go to Step 10
81. Repair the wire between the fuel pump relay
connector terminal 86 and the ignition key ON
(IGN1).
2. Install the fuel pump relay.
3. Turn the ignition OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 10
91. Repair the wire between the fuel pump relay
connector terminal 85 and the ECM connector
terminal 6.
2. Install the fuel pump relay.
3. Turn the ignition OFF for 10 seconds.
4. Clear any DTCs from ECM.
5. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 10

1F – 294IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
101. Replace the ECM.
2. Turn the ignition OFF for 10 seconds.
3. Clear any DTCs from ECM.
4. Turn the ignition switch to ON.
Does the fuel pump operate?2.55 secondsSystem OKGo to Step 11
111. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC ad specified in the supporting
text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 12Go to Step 2
12Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
applicable DTC
tableSystem OK

ENGINE CONTROLS 1F – 295
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P1320
CRANKSHAFT SEGMENT PERIOD SEGMENT
ADAPTATION AT LIMIT
Circuit Description
The 58X reference signal is produced by the Crankshaft
Position (CKP) sensor. During one crankshaft revolution,
58 crankshaft pulses will be produced. The Engine Control
Module (ECM) uses the 58X reference signal to calculate
engine rpm and CKP. The ECM constantly monitors the
number of pulses on the 58X reference circuit and
compares them to the number of Camshaft Position
(CMP) signal pulses being received. If the ECM receives
and incorrect number of pulses on the 58X reference cir-
cuit, Diagnostic Trouble Code (DTC) P1320 will set.
Conditions for Setting the DTC
S Segment adaptation valve at the limit.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive trip with a fail.
S The ECM will record operating conditions at the
time the diagnostic fail. This information will be
stored in the Freeze Frame and Failure Records
buffers.
S A history DTC is stored.
Conditions for Clearing the MIL/DTC
S The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.S A history DTC will clear after 40 consecutive warm–
up cycles without a fault.
S DTC(s) can be cleared by using the scan tool.
S Disconnecting the ECM battery feed for more than
10 seconds.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for:
S Poor connection – Inspect the ECM harness and
connectors for improper mating, broken locks, im-
properly formed or damaged terminals, and poor
terminal–to–wire connections.
S Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, discon-
nect the ECM, turn the ignition ON and observe a
voltmeter connected to the 58X reference circuit at
the ECM harness connector while moving the con-
nectors and the wiring harnesses related to the
ECM. A change in voltage will indicate the location
of the fault.
S Reviewing the Failure Records vehicle mileage
since the diagnostic test last failed may help deter-
mine how often the condition that caused the DTC
to be set occurs. This may assist in diagnosing the
condition.
DTC P1320 – Crankshaft Segment Period Segment Adaptation at
Limit
StepActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Was the check performed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
2Attempt to start the engine.
Does the engine start?–Go to Step 3Refer to
”Engine Cranks
But Will Not
Run”
31. Turn the ignition OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Turn the ignition ON, with the engine OFF.
4. Review and record Failure Records informa-
tion.
5. Clear the Diagnostic Trouble Codes (DTCs).
6. Start the engine and idle for 1 minute.
Is DTC P1320 set?–Go to Step 4Go to
”Diagnostic
Aids”

1F – 296IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
41. Remove the crankshaft.
2. Check for a problem with the crahkshaft’s visu-
al defection and tooth.
Is a problem found?–Go to Step 5Go to Step 6
5Replace the crankshaft.
Is the replacement complete?–System OK–
61. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 7–
71. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating
temperature.
3. Operate the vehicle within the conditions for
setting this DTC as supported in the text.
Does the scan tool indicate that this diagnostic ran
and passed?–Go to Step 8Go to Step 2
8Check if any additional DTCs are set.
Are any DTCs displayed that have not been diag-
nosed?–Go to
Applicable DTC
tableSystem OK