1998 ISUZU TROOPER sensor

6E±194
ENGINE DRIVEABILITY AND EMISSIONS

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 58X reference circuit at the PCM
harness connector while moving connectors and
wiring harnesses related to the ICM. A change in
voltage will indicate the location of the fault.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.
DTC P0336 ± 58X Reference Signal Circuit

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Attempt to start the engine.
Does the engine start?
ÐGo to Step 3
Go to ªEngine
Cranks But
Will Not Runº
chart
31. Review and record Failure Records information.
2. Clear DTC P0336.
3. Start the engine and idle for 1 minute.
4. Observe DTCs.
Is DTC P0336 set?
ÐGo to Step 4
Refer to
Diagnostic
Aids
41. Disconnect the PCM and CKP sensor.
2. Check for an open or a short to ground in the 58X
reference circuit between the CKP sensor
connector and the PCM harness connector.
3. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 5
51. Reconnect the PCM and CKP sensor.
2. Connect a DVM to measure voltage on the 58X
reference circuit at the PCM connector.
3. Observe the voltage while cranking the engine.
Is the voltage near the specified value?
2.5 VGo to Step 8Go to Step 6
6Check the connections at the CKP sensor and replace
the terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 7
7Replace the CKP sensor. Use caution to avoid any hot
oil that may drip out.
Is the action complete?
ÐVerify repairÐ
8Check connections at the PCM and replace the
terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 9
9Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?ÐVerify repairÐ

6E±195 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0337 CKP Sensor Circuit Low Frequency
D06RW032
Circuit Description
The 58X reference signal is produced by the crankshaft
position (CKP) sensor. During one crankshaft revolution,
58 crankshaft reference pulses will be produced. The
powertrain control module (PCM) uses the 58X reference
signal to calculate engine RPM and crankshaft position.
The PCM 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 PCM does not receive pulses on the 58X
reference circuit, DTC P0337 will set.
Conditions for Setting the DTC

No camshaft position (CMP) sensor DTCs are set.

Engine cranking.

Crankshaft position (CKP) sensor signal is not present
between two cam pulses.

CKP reference pulse is not detected within 8 CMP
pulses.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

DTC P0337 can be cleared by using Tech 2 ªClear Infoº
function or by disconnecting the PCM battery feed.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation. Check for:

Poor connection ± Inspect the PCM harness and
connectors for improper mating, broken locks,
improperly formed or damaged terminals, and poor
terminal-to-wire connection.

6E±196
ENGINE DRIVEABILITY AND EMISSIONS

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 58X reference circuit at the PCM
harness connector while moving connectors and
wiring harnesses related to the ICM. A change in
voltage will indicate the location of the fault.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.
DTC P0337 ± CKP Sensor Circuit Low Frequency

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Attempt to start the engine.
Does the engine start?
ÐGo to Step 3Go to Chart 3
31. Review and record Failure Records information.
2. Clear DTC P0337.
3. Start the engine and idle for 1 minute.
4. Observe DTCs.
Is DTC P0337 set?
ÐGo to Step 4
Refer to
Diagnostic
Aid
41. Disconnect the CKP sensor.
2. Ignition ªON.º
3. Using a DVM, verify that 5 V reference and ground
are being supplied at the sensor connector (PCM
side).
Are 4-6 volts and ground available at the sensor?
ÐGo to Step 7Go to Step 5
51. Ignition ªON.º
2. With a DVM, backprobe the PCM connector 5 V
reference and ground connections.
Are 5 V reference and ground available at the PCM?
ÐGo to Step 6Go to Step 11
6Check 5 V reference or ground between the CKP
sensor and PCM and repair the open circuit, short to
ground or short to voltage.
Is the action complete?
ÐVerify repairÐ
71. Ignition ªOFF.º
2. Disconnect the PCM and CKP sensor.
3. Check for an open or a short to ground in the 58X
reference circuit between the CKP sensor
connector and the PCM harness connector.
4. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
81. Reconnect the PCM and CKP sensor.
2. Connect a DVM to measure voltage on the 58X
reference circuit at the PCM connector.
3. Observe the voltage while cranking the engine.
Is the voltage near the specified value?
2.5 VGo to Step 11Go to Step 9
9Check the connections at the CKP sensor and replace
the terminals if necessary.
Did any terminals require replacement?
ÐVerify repairGo to Step 10
10Replace the CKP sensor. Use caution and avoid hot oil
that may drip out.
Is the action complete?
ÐVerify repairÐ

6E±197 ENGINE DRIVEABILITY AND EMISSIONS
DTC P0337 ± CKP Sensor Circuit Low Frequency

 
StepNo Ye s Value(s) Action
11Check the connections at the PCM and replace the
terminals if necessary.
Did any terminals require replacement?
ÐVerify repair Go to Step 12
12Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?ÐVerify repairÐ

6E±198
ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0341 CMP Sensor Circuit Performance
D06RW032
Circuit Description
The CMP signal is produced by the camshaft position
(CMP) sensor pulses when the engine is running and
crankshaft position (CKP) sync pulses are also being
received. The powertrain control module (PCM) uses the
CMP signal pulses to initiate sequential fuel injection.
The PCM constantly monitors the number of pulses on
the CMP signal circuit and compares the number of CMP
pulses to the number of 58X reference pulses received. If
the PCM receives an incorrect number of pulses on the
CMP reference circuit, DTC P0341 will set and the PCM
will initiate injector sequence without the CMP signal with
a one in six chance that injector sequence is correct. The
engine will continue to start and run normally, although
the misfire diagnostic will be affected if a misfiring
condition occurs.
Conditions for Setting the DTC

The engine is running (1X CMP reference pulses are
being received).

The CMP sensor signal is not detected at the correct
interval every 6 cylinders.

Above condition fails for 100 occurrences within 200
test samples.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

The PCM will initiate the injector sequence without the
CMP signal with a one in six chance that the injector
sequence is correct.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

6E±199 ENGINE DRIVEABILITY AND EMISSIONS
Conditions for Clearing the MIL/DTC

DTC P0341 can be cleared by using Tech 2 ªClear Infoº
function or by disconnecting the PCM battery feed.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside the
insulation. Check for:

Poor connection ± Inspect the PCM harness and
connectors for 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 CMP signal circuit at the PCM
harness connector while moving connectors andwiring harnesses related to the ICM and the CMP
sensor. A change in voltage will indicate the location
of the fault.
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.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Ensures that the fault is present.
12.Determines whether the fault is being caused by a
missing camshaft magnet or a faulty sensor. The
voltage measured in this step should read around 4
volts, toggling to near 0 volts when the CMP sensor
interfaces with the camshaft magnet.

6E±200
ENGINE DRIVEABILITY AND EMISSIONS
DTC P0341 ± CMP Sensor Circuit Performance

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªON.º
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using Tech 2, monitor ªSpecific DTCº info for DTC
P0341 until the DTC P0341 test runs.
5. Note the test result.
Does Tech 2 indicate DTC P0341 failed this ignition?
ÐGo to Step 3
Refer to
Diagnostic
Aids
31. Disconnect the CMP sensor.
2. Measure the voltage between the sensor feed
circuit and the sensor ground circuit at the CMP
sensor harness connector.
Does the voltage measure near the specified value?
4-6 VGo to Step 4Go to Step 5
4Measure the voltage between the CMP sensor signal
circuit and the sensor ground circuit at the CMP sensor
harness connector.
Does the voltage measure near the specified value?
4-6 VGo to Step 11Go to Step 8
5If the voltage measured in step 3 was less than 4-6
volts, proceed directly to step 6 without completing this
step.
If the voltage in step 3 was greater than 4-6 V, repair the
short to voltage in the CMP feed circuit.
Is the action complete?
ÐVerify repairÐ
61. Check for poor connections at the camshaft
position sensor.
2. If a problem is found, repair it as necessary.
Was a problem found?
ÐVerify repairGo to Step 7
71. Ignition ªOFF,º disconnect the PCM and the CMP
sensor.
2. Check the following circuits for an open between the
ignition coil and the CMP sensor:

The sensor feed circuit.
3. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repair Go to Step 9
81. Ignition ªOFF,º disconnect the PCM (leave the CMP
sensor disconnected).
2. Ignition ªON,º check the following circuits:

The CMP sensor signal circuit for an open or a
short to voltage.

The CMP sensor input signal circuit for a short
to ground.
3. If a problem is found, repair it as necessary.
Was a problem found?
ÐVerify repairGo to Step 9
9Check for a short or open in the sensor ground circuit.
Was a problem found?
ÐVerify repairGo to Step 10

6E±201 ENGINE DRIVEABILITY AND EMISSIONS
DTC P0341 ± CMP Sensor Circuit Performance

 
StepNo Ye s Value(s) Action
101. Check for poor connections at the PCM.
2. If a problem is found, repair it as necessary.
Was a problem found?
ÐVerify repairGo to Step 11
11Backprobe the PCM connector with a DVM to monitor
voltage on the camshaft position input signal circuit
while cranking the engine with the sensor connected.
(Use rubber band, tape, or an assistant to keep the
DVM lead in contact with the sensor terminal during this
test.)
Does the voltage toggle between the specified values?
4-0 VGo to Step 15Go to Step 12
121. Remove the CMP sensor from the engine front
cover (leave the sensor wiring connected).
2. Place a magnet on the CMP sensor.
(If you use a magnet that is too small to cover the face
of the sensor, test on every part of the sensor face
because only a small area will respond to this test.)
Does the DVM display a voltage near the specified
value?
0 VGo to Step 13Go to Step 14
13Replace the faulty or missing camshaft position sensor
magnet.
Is the action complete?
ÐVerify repairÐ
14Replace the camshaft position sensor.
Is the action complete?
ÐVerify repairÐ
15Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
UBS 98model year Immobilizer
Workshop Manual.
Is the action complete?ÐVerify repairÐ