TEST ACTION APPLICABILITY
5 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between ground and O2 Sensor harness connector cavities 1,
2, 3, 5, and 6.
Is the resistance above 1000 ohms for each measurement?All
Ye s!Go To 6
No!Repair the circuit(s) that measured below 1000 ohms for a short to
ground.
Perform ROAD TEST VERIFICATION - VER-2.
6 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the ECM harness connectors.
NOTE: The circuits connecting the O2 Sensor and the ECM are single
circuits and do not contain any splices. There should be NO continuity from
one circuit to the other.
Using an ohmmeter, check the O2 Sensor circuits for shorts together (resistance
below 1000 ohms)..
Is the resistance from any O2 Sensor circuit to another below 1000 ohms?All
Ye s!Repair the circuits that measured below 1000 ohms for a short
together.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 7
7 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the ECM harness connectors.
Remove the Engine Control Relay.
Connect a jumper wire between cavity 30 and cavity 87 of the Engine Control Relay
connector.
Turn the ignition on.
Measure the voltage of O2 Sensor harness connector cavities 1, 2, 3, 5, and 6.
Is the voltage below 1.0 volts for each measurement?All
Ye s!Go To 8
No!Repair the circuit(s) that measured below 1000 ohms for a short to
voltage.
Perform ROAD TEST VERIFICATION - VER-2.
8 Turn the ignition off.
Replace the O2 Sensor in accordance with the Service Information.
Turn the ignition on.
With the DRBIIIt, erase the ECM DTCs.
Test drive the vehicle.
With the DRBIIIt, read the ECM DTCs.
Did this DTC set again?All
Ye s!Replace the ECM in accordance with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Test Complete.
136
DRIVEABILITY - DIESEL
P2026-O2 SENSOR CIRCUIT FAULT ÐContinued
TEST ACTION APPLICABILITY
9WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DTC When Monitored and Set Conditions. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s!Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No!Test Complete.
137
DRIVEABILITY - DIESEL
P2026-O2 SENSOR CIRCUIT FAULT ÐContinued
Symptom List:
P2034-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO HIGH
P2034-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO LOW
P2036-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO HIGH
P2036-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO LOW
P2038-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO HIGH
P2038-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO LOW
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P2034-O2 SENSOR CIRCUIT
CALIBRATION VALUE TOO HIGH.
POSSIBLE CAUSES
CHECKING CIRCUIT INTEGRITY
O2 SENSOR
INTERMITTENT CONDITION
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Using the Service Information wiring diagrams, inspect the wiring and connectors
between the ECM and the O2 sensor for damage, corrosion, poor terminal contact or
other problems.
Were any problems found?All
Ye s!Clean, repair or replace as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 2
2NOTE: If the ECM detects and stores a DTC, the ECM also stores the
engine/vehicle operating conditions under which the DTC was set. Some of
these conditions are displayed on the DRB at the same time the DTC is
displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to
duplicate these conditions may assist when checking for an active DTC.
Turn the ignition on.
With the DRB, erase ECM DTCs.
Turn the ignition off for 10 seconds.
Test drive the vehicle.
Monitor the DRB for ECM DTCs.
Did this DTC set again?All
Ye s!Replace the Oxygen Sensor.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 3
138
DRIVEABILITY - DIESEL
TEST ACTION APPLICABILITY
3WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DTC When Monitored and Set Conditions. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s!Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No!Test Complete.
139
DRIVEABILITY - DIESEL
P2034-O2 SENSOR CIRCUIT CALIBRATION VALUE TOO HIGH Ð
Continued
Symptom List:
P2043-CAMSHAFT POSITION SENSOR CIRCUIT OPEN CIRCUIT
P2043-CAMSHAFT POSITION SENSOR CIRCUIT OPEN OR SHORT
CIRCUIT
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P2043-CAMSHAFT POSITION
SENSOR CIRCUIT OPEN CIRCUIT.
POSSIBLE CAUSES
5-VOLT SUPPLY CIRCUIT OPEN
CAMSHAFT POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
CHECKING 5-VOLT SUPPLY CIRCUIT
DAMAGED CMP SENSOR OR CAMSHAFT
ECM
ECM
ECM - CAMSHAFT POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
SENSOR GROUND CIRCUIT OPEN
INTERMITTENT CONDITION
CMP SENSOR SIGNAL CIRCUIT OPEN
5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
CMP SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
CMASHAFT POSITION SENSOR
ECM SENSOR GROUND CIRCUIT OPEN
5-VOLT SUPPLY CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT
CMP SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT
140
DRIVEABILITY - DIESEL
TEST ACTION APPLICABILITY
1NOTE: If DTC P1611, P2306 or P2332 is present with this DTC, diagnose
DTCs P1611, P2306 or P2332 before diagnosing this DTC.
NOTE: The Timing Belt/Chain must be correctly installed and operational
before diagnosis can be made. Refer to the Service Information to ensure
the timing belt is properly installed.
NOTE: If the ECM detects and stores a DTC, the ECM also stores the
engine/vehicle operating conditions under which the DTC was set. Some of
these conditions are displayed on the DRB at the same time the DTC is
displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to
duplicate these conditions may assist when checking for an active DTC.
Turn the ignition on.
With the DRBIIIt, erase the ECM DTCs.
Attempt to start the engine cranking the engine for at least 7 seconds.
With the DRBIIIt, read the ECM DTCs.
Does the DRBIIItdisplay this DTC?All
Ye s!Go To 4
No!Go To 2
2 Turn the ignition on.
With the DRBIIIt, erase the ECM DTCs.
Test drive the vehicle.
With the DRBIIIt, read the ECM DTCs.
Does the DRBIIItdisplay this DTC?All
Ye s!Go To 3
No!Go To 16
3 Turn the ignition off.
Disconnect the Camshaft Position Sensor harness connector.
Turn the ignition on.
Measure the voltage of the CMP Sensor Signal circuit.
Select the appropriate voltage reading.All
Voltage is above 5.4 volts.
Go To 4
Voltage is between 4.7 and 5.4 volts.
Go To 5
Voltage is below 4.7 volts.
Go To 13
141
DRIVEABILITY - DIESEL
P2043-CAMSHAFT POSITION SENSOR CIRCUIT OPEN CIRCUIT Ð
Continued
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the Camshaft Position Sensor harness connector.
Disconnect the ECM harness connectors.
Remove the Engine Control Relay.
Connect a jumper wire between cavity 30 and cavity 87 of the Engine Control Relay
connector.
Turn the ignition on.
Measure the voltage of the CMP Position Sensor Signal circuit.
Is the voltage below 1.0 volt?All
Ye s!Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Repair the Camshaft Position Sensor Signal circuit for a short to
voltage.
Perform ROAD TEST VERIFICATION - VER-2.
5 Turn the ignition off.
Disconnect the Camshaft Position Sensor harness connector.
Turn the ignition on.
Measure the voltage of the CMP Sensor 5-Volt Supply circuit.
Select the appropriate voltage reading.All
Voltage is above 5.4 volts.
Repair the CMP 5-Volt Supply circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
Voltage is between 4.7 and 5.4 volts.
Go To 6
Voltage is below 4.7 volts.
Go To 10
6 Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the Sensor Ground circuit between the CMP Sensor
harness connector and the ECM harness connector.
Is the resistance below 10.0 ohms?All
Ye s!Go To 7
No!Repair the Sensor Ground circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
7 Turn the ignition on.
Disconnect the ECT Sensor harness connector.
Disconnect the Camshaft Position Sensor harness connector.
Connect one end of a jumper wire to the ECT Sensor signal circuit in the ECT Sensor
harness connector.
Connect the other end of the jumper wire to the Sensor Ground circuit in the
Camshaft Position Sensor harness connector.
With the DRBIIItin Engine, Sensors, read the Engine Coolant Temp volts.
Is the voltage below 0.5 volt?All
Ye s!Go To 8
No!Replace and program the ECM in accordance with the Service
Information.
Perform ROAD TEST VERIFICATION - VER-2.
142
DRIVEABILITY - DIESEL
P2043-CAMSHAFT POSITION SENSOR CIRCUIT OPEN CIRCUIT Ð
Continued
TEST ACTION APPLICABILITY
8 Turn the ignition off.
Remove the CMP Sensor.
Inspect the CMP Sensor for conditions such as loose mounting screws, damage, or
cracks.
Inspect the camshaft for conditions such as damage, debris or cracked teeth.
Is there any evidence of these conditions?All
Ye s!Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 9
9 Turn the ignition off.
With the DRBIIItlab scope lead, backprobe the CMP Signal circuit.
Set the DRBIIItlab scope settings as follows: Time = 0.2s/Div, 20 volts scale, Offset
= 0.00 volts, Probe = X10, Coupling = DC.
While observing the DRBIIItdisplay, crank the engine.
NOTE: The DRBIIItshould display a digital signal (square wave) similar to
that shown in Charts and Graphs.
Does the DRBIIItdisplay an uninterrupted digital signal (square wave)?All
Ye s!Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Replace the Camshaft Position Sensor in accordance with the
Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
10 Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the CMP Sensor harness connector.
Measure the resistance of the 5-Volt Supply circuit between the ECM harness
connector and the CMP Sensor harness connector.
Is the resistance below 10.0 ohms?All
Ye s!Go To 11
No!Repair the 5-Volt Supply circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
11 Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the CMP Sensor 5-Volt Supply circuit.
Is the resistance above 1000 ohms?All
Ye s!Go To 12
No!Repair the CMP Sensor 5-Volt Supply circuit for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
143
DRIVEABILITY - DIESEL
P2043-CAMSHAFT POSITION SENSOR CIRCUIT OPEN CIRCUIT Ð
Continued