
1F – 452IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0336
58X CRANK POSITION SENSOR EXTRA/MISSING
PULSES
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) P0336 will set.
Conditions for Setting the DTC
S Engine is running.
S Extra or missing pulses detected between consecu-
tive 58X reference pulses.
S Number of extra or missing teeth is greater than or
equal to 2 per revolution.
S Above condition is detected in 10 of 100 crankshaft
rotations.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
S The ECM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Freeze Frame and Failure Records
buffer.
S A history DTC is stored.
Conditions for Clearing the MIL/DTCS The MIL will turn OFF after four consecutive igni-
tion cycles in which the diagnostic runs without a
fault.
S A history DTC will clear after 40 consecutive warm–
up cycles have occurred without a fault.
S The DTC(s) can be cleared 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–towire 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.

ENGINE CONTROLS 1F – 455
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0337
58X CRANK POSITION SENSOR NO SIGNAL
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 does not
receive any 58X reference pulses on the 58X reference
circuit while cranking, Diagnostic Trouble Code (DTC)
P0337 will set.
Conditions for Setting the DTC
S 58X reference pulse not seen during cranking.
S DTCs P0341 and P0342 are not set.
S Change in voltage drop is greater than 0.5 volts and
change in Manifold Absolute Pressure (MAP) is
greater than 0.05kPa (0.07 psi).
S 58X reference pulse not seen for 0.078 seconds.
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 Failure Records
buffer.
S A history DTC is stored.
Conditions for Clearing the MIL/DTCS The MIL will turn OFF after four consecutive igni-
tion cycles in which the diagnostic runs without a
fault.
S A history DTC will clear after 40 consecutive warm–
up cycles have occurred without a fault.
S The DTC(s) can be cleared 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–towire 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.

1F – 456IENGINE CONTROLS
DAEWOO V–121 BL4
DTC P0337 – 58X Crank Position Sensor No Signal
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Was the check performed?–Go to Step 2Go to
”On–Board
Diagnostic Sys-
tem Check”
21. Turn the ignition OFF.
2. Install a scan tool to the Data Link Connector
(DLC).
3. Start the engine.
4. Operate the vehicle within the Freeze Frame
conditions and Conditions for Setting the DTC
as noted.
Is Diagnostic Trouble Code (DTC) P0337 set?–Go to Step 3Go to Step 10
31. Turn the ignition OFF.
2. Disconnect the Crankshaft Position (CKP) sen-
sor connector.
3. Turn the ignition ON.
4. Using a voltmeter, check the voltage between
the CKP sensor wiring harness connector (En-
gine Control Module [ECM] side) terminal 1
and ground.
Does the voltage within the value specified?1.4 voltsGo to Step 4Go to Step 5
4Using a voltmeter, check the voltage between the
CKP sensor wiring harness connector (ECM side)
terminal 2 and ground.
Does the voltage within the value specified?1.4 voltsGo to Step 6Go to Step 5
51. Turn the ignition OFF.
2. Disconnect the ECM connector.
3. Turn the ignition ON.
4. Using a voltmeter, check the out put voltage of
the ECM terminal M21 and M5.
Does the voltage within the value specified?11–14 voltsGo to Step 8Go to Step 9
61. Reconnect the CKP sensor.
2. Using a voltmeter, back probe the ECM con-
nector terminal M21 and M5.
3. Observe the voltage while cranking the engine.
Does the voltage fluctuate between the specified
value?1.3–1.6 voltsGo to
”Diagnostic
Aids”Go to Step 7
71. Turn the ignition OFF.
2. Replace the CKP sensor.
Is the repair complete?–Go to Step 10–
8Check the CKP sensor high and low circuits for an
open, short to ground or voltage and repair as need-
ed.
Is the repair complete?–Go to Step 10–
91. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?–Go to Step 10–

1F – 458IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0341
CAMSHAFT POSITION SENSOR RATIONALITY
System Description
The Camshaft Position (CMP) Sensor is used to correlate
crankshaft to camshaft position so that the Engine Control
Module (ECM) can determine which cylinder is ready to be
fueled by the injector. The CMP is also used to determine
which cylinder is misfiring when a misfire is present. When
the ECM cannot use the information from the CMP sensor,
a Diagnostic Trouble Code (DTC) is set, and the ECM will
fuel the engine using the Alternating Synchronous Double
Fire (ASDF) method.
Conditions for Setting the DTC
S CMP Sensor reference pulse is not detected at the
correct interval every 4 cylinders.
S Engine is running.
Action Taken When the DTC Sets
S The Malfunction Indicator Lamp (MIL) will illuminate
after three consecutive ignition cycle with a fail.
S The ECM will record operating conditions at the
time the diagnostic fails. 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 problem may be caused by a poor connec-
tion, rubbed–through wire insulation, or a wire that is bro-
ken 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 terminal–to–wire connection
S Physical damage to the wiring harness
Anytime a poor connection is present, the CMP Reference
Activity counter will stop incrementing.

ENGINE CONTROLS 1F – 461
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0342
CAMSHAFT POSITION SENSOR NO SIGNAL
System Description
The Camshaft Position (CMP) Sensor is used to correlate
crankshaft to camshaft position so that the Engine Control
Module (ECM) can determine which cylinder is ready to be
fueled by the injector. The CMP is also used to determine
which cylinder is misfiring when a misfire is present. When
the ECM cannot use the information from the CMP sensor,
a Diagnostic Trouble Code (DTC) is set, and the ECM will
fuel the engine using the Alternating Synchronous Double
Fire (ASDF) method.
Conditions for Setting the DTC
S CMP Sensor pulse is not detected at the correct
interval every 4 cylinders.
S Engine is running.
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 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 problem may be caused by a poor connec-
tion, rubbed–through wire insulation, or a wire that is bro-
ken 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 terminal–to–wire connection
S Physical damage to the wiring harness
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Table.

ENGINE CONTROLS 1F – 577
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
101. Check the fuel injector driver circuit.
2. Disconnect all of the fuel injector harness con-
nectors at the fuel injectors.
3. Connect an injector test light between the har-
ness terminals of each fuel injector connector.
4. Note the test light while cranking the engine.
Does the test light blink at all connectors?–Go toStep 13Go toStep 11
11Check the fuel injector driver wiring harness, the
connectors, and the connector terminals for the
proper connections.
Is the problem found?–Go toStep 12Go toStep 30
12Repair the wiring harness, the connector, or the con-
nector terminal as needed.
Is the repair complete?–System OK
13Measure the resistance of each fuel injector at 68°F
(20°C). The resistance will increase slightly at high-
er temperatures.
Is the fuel injector resistance within the value speci-
fied?11.6–12.4 ΩGo toStep 15Go toStep 14
14Replace any fuel injector with a resistance that is out
of specifications.
Is the repair complete?–System OK–
15Perform an injector balance test.
Is the problem found?–Go toStep 16Go toStep 17
16Replace any restricted or leaking fuel injectors as
needed.
Is the repair complete?–System OK–
171. Check for the proper ignition voltage output for
each cylinder with a spark tester.
2. Inspect the spark plugs for cracks, wear, im-
proper gap, burned electrodes, or heavy de-
posits.
3. Inspect the ignition wires for short conditions.
4. Inspect all of the ignition grounds for loose con-
nections.
5. Inspect the powertrain control module
(PCM)/engine control module (ECM) for the
proper operation.
Is the problem found?–Go toStep 18Go toStep 19
18Correct or replace any faulty ignition components.
Is the repair complete?–System OK–
19Does the engine misfire or cut out under load or at
idle?Go to
”Ignition Sys-
tem Check”Go toStep 20
20Does the engine start, but then immediately stall?–Go toStep 21Go toStep 23
211. Remove the Crankshaft Position (CKP) sensor.
2. Inspect for faulty connections and repair as
needed.
Is the problem found?–Go toStep 22Go toStep 25
22Repair the faulty connections as needed.
Is the repair complete?–System OK–

ENGINE CONTROLS 1F – 633
DAEWOO V–121 BL4
Failed This Ig. (Failed This Ignition)
This message display indicates that the diagnostic test
has failed at least once during the current ignition cycle.
This message will clear when DTCs are cleared or the igni-
tion is cycled.
History
This message display indicates that the DTC has been
stored in memory as a valid fault. A DTC displayed as a
History fault may not mean that the fault is no longer pres-
ent. The history description means that all the conditions
necessary for reporting a fault have been met (maybe
even currently), and the information was stored in the con-
trol module memory.
MIL Requested
This message display indicates that the DTC is currently
causing the MIL to be turned ON. Remember that only
type A and type B DTCs can request the MIL. The MIL re-
quest cannot be used to determine if the DTC fault condi-
tions are currently being experienced. This is because the
diagnostic executive will require up to three trips during
which the diagnostic test passes to turn OFF the MIL.
Not Run Since CI (Not Run Since Cleared)
This message display indicates that the selected diagnos-
tic test has not run since the last time DTCs were cleared.
Therefore, the diagnostic test status (passing or failing) is
unknown. After DTCs are cleared, this message will con-
tinue to be displayed until the diagnostic test runs.
Not Run This Ig. (Not Run This Ignition)
This message display indicates that the selected diagnos-
tic test has not run during this ignition cycle.
Test Ran and Passed
This message display indicates that the selected diagnos-
tic test has done the following:
S Passed the last test.
S Run and passed during this ignition cycle.
S Run and passed since DTCs were last cleared.
If the indicated status of the vehicle is ”Test Ran and
Passed” after a repair verification, the vehicle is ready to
be released to the customer.
If the indicated status of the vehicle is ”Failed This Ignition”
after a repair verification, then the repair is incomplete and
further diagnosis is required.
Prior to repairing a vehicle, status information can be used
to evaluate the state of the diagnostic test, and to help
identify an intermittent problem. The technician can con-
clude that although the MIL is illuminated, the fault condi-
tion that caused the code to set is not present. An intermit-
tent condition must be the cause.
PRIMARY SYSTEM – BASED
DIAGNOSTICS
There are primary system–based diagnostics which eval-
uate system operation and its effect on vehicle emissions.
The primary system–based diagnostics are listed below
with a brief description of the diagnostic function:
Oxygen Sensor Diagnosis
The fuel control Front Heated Oxygen Sensor (HO2S1) is
diagnosed for the following conditions:
S Slow response.
S Response time (time to switch R/L or L/R).
S Inactive signal (output steady at bias voltage
approx. 450 mv).
S Signal fixed high.
S Signal fixed low.
The catalyst monitor Rear Heated Oxygen Sensor
(HO2S2) is diagnosed for the following conditions:
S Heater performance (time to activity on cold start).
S Signal fixed low during steady state conditions or
power enrichment (hard acceleration when a rich-
mixture should be indicated).
S Signal fixed high during steady state conditions or
deceleration mode (deceleration when a lean mix-
ture should be indicated).
S Inactive sensor (output steady at approximately 438
mv).
If the oxygen sensor pigtail wiring, connector or terminal
are damaged, the entire oxygen sensor assembly must be
replaced. Do not attempt to repair the wiring, connector or
terminals. In order for the sensor to function properly, it
must have clean reference air provided to it. This clean air
reference is obtained by way of the oxygen sensor wire(s).
Any attempt to repair the wires, connector or terminals
could result in the obstruction of the reference air and de-
grade oxygen sensor performance.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft
rotational velocity (reference period) variations. The en-
gine control module (ECM) determines crankshaft rota-
tional velocity using the Crankshaft Position (CKP) sensor
and the Camshaft Position (CMP) sensor. When a cylinder
misfires, the crankshaft slows down momentarily. By mon-
itoring the CKP and CMP sensor signals, the ECM can cal-
culate when a misfire occurs.
For a non–catalyst damaging misfire, the diagnostic will be
required to monitor a misfire present for between
1000–3200 engine revolutions.
For catalyst–damaging misfire, the diagnostic will respond
to misfire within 200 engine revolutions.
Rough roads may cause false misfire detection. A rough
road will cause torque to be applied to the drive wheels and
drive train. This torque can intermittently decrease the
crankshaft rotational velocity. This may be falsely de-
tected as a misfire.