TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the Fuel Pressure Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the Sensor Ground circuit.
Is the resistance below 10.0 ohms?All
Ye s!Go To 5
No!Repair the Sensor Ground circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
5 Turn the ignition off.
Disconnect the Fuel Pressure Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the Fuel Pressure Sensor 5-Volt Supply circuit.
Is the resistance below 10.0 ohms?All
Ye s!Go To 6
No!Repair the Fuel Pressure Sensor 5-volt Supply circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
6 Turn the ignition off.
Disconnect the Fuel Pressure 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 Sensor Ground circuit at the Fuel Pressure Sensor and
ECM harness connectors.
Is the voltage above 1.0 volt at either connector?All
Ye s!Repair the Sensor Ground circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 7
NOTE: If the Sensor Ground circuit had a short to voltage on it, the ECM
could be damaged. Retest the Fuel Pressure Sensor circuit.
7 Turn the ignition off.
Disconnect the Fuel Pressure Sensor harness connector.
Connect a jumper wire between the Fuel Pressure Sensor Signal circuit and the
Sensor Ground circuit in the Fuel Pressure Sensor harness connector.
Turn the ignition on and monitor the DRB for DTCs.
Is DTC P0190 FUEL PRESS SENSOR CIRCUIT MALF SIGNAL VOLTAGE TOO
LOW present?All
Ye s!Replace the Fuel Pressure Sensor.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 8
8 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
55
DRIVEABILITY - DIESEL
P0190-FUEL PRESS SENSOR CIRCUIT MALF SIGNAL VOLTAGE TOO
HIGH Ð
Continued
P0205-CYLINDER 5-INJECTOR CIRCUIT SHORTED TO GROUND
When Monitored: With the engine running.
Set Condition: The ECM detects a short to ground on the Cylinder #5 Injector circuit.
P0205-CYLINDER 5-INJECTOR CIRCUIT SHORTED TO VOLTAGE
When Monitored: With the engine running.
Set Condition: The ECM detects a short to voltage on the Cylinder #5 Injector circuit.
POSSIBLE CAUSES
CHECKING ECM POWER AND GROUNDS
CHECKING THE ENGINE CONTROL RELAY SYSTEM
ENGINE CONTROL MODULE
INTERMITTENT CONDITION
FUEL INJECTOR CONTROL CIRCUIT SHORTED TO VOLTAGE
FUEL INJECTOR CONTROL CIRCUIT SHORTED TO GROUND
FUEL INJECTOR CIRCUITS SHORTED TOGETHER
FUEL INJECTOR CONTROL CIRCUIT OPEN
FUEL INJECTOR
TEST ACTION APPLICABILITY
1NOTE: 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 and test drive the vehicle.
With the DRBIIIt, read the ECM DTCs.
Did this DTC set again?All
Ye s!Go To 2
No!Go To 8
63
DRIVEABILITY - DIESEL
P0201-CYLINDER 1-INJECTOR CIRCUIT EXCESSIVE CURRENT Ð
Continued
TEST ACTION APPLICABILITY
2 Turn the ignition off.
Disconnect the ECM harness connectors.
Connect a jumper wire between ground and the Engine Control Relay Control circuit
in ECM C2 harness connector cavity 44.
Turn the ignition on.
Using a 12-volt test light connected to ground, check the Fused Engine Control Relay
Output circuits at the ECM C2 harness connector cavities 1, 3 and 5.
Choose the appropriate result.All
Test light is on for all circuits.
Go To 3
Test light is on for 1 or 2 circuits
Repair the Engine Control Relay Output circuit(s) that did not
illuminate brightly for an open.
Perform ROAD TEST VERIFICATION - VER-2.
Light off for all circuits.
Refer to symptom Checking the ECM Power and Grounds.
Perform ROAD TEST VERIFICATION - VER-2.
3 Turn the ignition off.
Disconnect all of the Cylinder Fuel Injector harness connectors.
Disconnect the ECM harness connectors.
Remove the Engine Control Relay from Fuse Block No.1
Connect a jumper wire between cavity 30 and cavity 87 of the Engine Control Relay
connector in Fuse Block No.1.
Turn the ignition on.
Measure the voltage of all of the Fuel Injector Control circuit.
Is the voltage above 1.0 volt for any of the measurements?All
Ye s!Repair the appropriate Fuel Injector Control circuit for a short to
voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 4
4 Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect all of the Fuel Injector harness connectors.
Measure the resistance between ground and all of the Fuel Injector Control circuit.
Is the resistance below 1000 ohms for any of the measurements?All
Ye s!Repair the Fuel Injector Control circuit for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 5
5 Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect all of the Cylinder Fuel Injector harness connectors.
Measure the resistance between Fuel Injector No. 1 harness connector cavities 1 and
2.
Repeat the previous step for injectors 2, 3, 4, and 5.
Is the resistance below 1000 ohms for any of the measurements?All
Ye s!Repair the Fuel Injector Control circuit and Common Driver
circuit for a short together.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 6
64
DRIVEABILITY - DIESEL
P0201-CYLINDER 1-INJECTOR CIRCUIT EXCESSIVE CURRENT Ð
Continued
TEST ACTION APPLICABILITY
4WARNING: 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 and 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 by slowly pressing and releasing the
accelerator pedal several times.
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.
5NOTE: Perform the rest of this diagnostic procedure on the individual APP
Sensor Potentiometer (1 or 2) that did not display the correct voltages in the
previous test.
Turn the ignition off.
Disconnect the APP Sensor harness connector.
Turn the ignition on.
Measure the voltage of the 5-Volt Supply circuit in the APP Sensor harness connector.
Is the voltage between 4.7 and 5.3 volts?All
Ye s!Go To 6
No!Go To 14
6 Turn the ignition off.
Disconnect the APP Sensor harness connector.
Connect a jumper wire between APP Sensor Signal circuit and the 5-volt supply
circuit at the APP Sensor harness connector .
With the DRB, read the PEDAL OUTPUT VOLTS.
Does the DRB display between 4.0 and 5.5 volts?All
Ye s!Go To 7
No!Go To 10
7 Turn the ignition off.
Disconnect the APP 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 APP Sensor Ground circuit.
Is the voltage above 1.0 volt?All
Ye s!Repair the App Sensor Ground circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 8
75
DRIVEABILITY - DIESEL
P1222-ACC PEDAL POSITION SENSOR 1 CKT PLAUSIBILITY ÐContinued
TEST ACTION APPLICABILITY
13 Turn the ignition off.
Disconnect the APP 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 APP Sensor Signal circuit.
Is the voltage above 1.0 volt?All
Ye s!Repair the APP Sensor Signal circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No!Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
14 Turn the ignition off.
Disconnect the APP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the Accelerator Pedal Position Sensor 5-volt Supply circuit.
Is the resistance below 10.0 ohms?All
Ye s!Go To 15
No!Repair the Accelerator Pedal Position Sensor 5-Volt Supply circuit
for an open.
Perform ROAD TEST VERIFICATION - VER-2.
15 Turn the ignition off.
Disconnect the APP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between the Accelerator Pedal Position Sensor 5-Volt Supply
circuit and both Sensor Ground circuits in the APP Sensor harness connector.
Is the resistance above 1000 ohms?All
Ye s!Go To 16
No!Repair the 5-Volt Supply circuit for a short to the Sensor Ground
circuit.
Perform ROAD TEST VERIFICATION - VER-2.
16 Turn the ignition off.
Disconnect the APP Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the Accelerator Pedal Position Sensor
5-volt Supply circuit.
Is the resistance below 1000 ohms?All
Ye s!Repair the Accelerator Pedal Position Sensor 5-Volt Supply circuit
for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 17
77
DRIVEABILITY - DIESEL
P1222-ACC PEDAL POSITION SENSOR 1 CKT PLAUSIBILITY ÐContinued
TEST ACTION APPLICABILITY
17 Turn the ignition off.
Disconnect the APP 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 Accelerator Pedal Position Sensor 5-Volt Supply circuit in
the ECM harness connector.
Is the voltage above 1.0 volt?All
Ye s!Repair the Accelerator Pedal Position Sensor 5-Volt Supply circuit
for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
No!Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
78
DRIVEABILITY - DIESEL
P1222-ACC PEDAL POSITION SENSOR 1 CKT PLAUSIBILITY ÐContinued
TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Glow Plug Module harness connectors.
Disconnect the ECM harness connectors.
Measure the resistance between ground and the Glow Plug Control Signal circuit.
Is the resistance above 1000 ohms?All
Ye s!Go To 4
No!Repair the Glow Plug Control Signal circuit for a short to ground.
Perform ROAD TEST VERIFICATION - VER-2.
4 Turn the ignition off.
Disconnect the Glow Plug Module harness connectors.
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.
Measure the voltage of the Glow Plug Control Signal circuit.
Is the voltage below 1.0 volt?All
Ye s!Go To 5
No!Repair the Glow Plug Control Signal circuit for a short to voltage.
Perform ROAD TEST VERIFICATION - VER-2.
5 Turn the ignition off.
Replace the Glow Plug Module in accordance with the Service Information.
Turn the ignition on.
With the DRBIIIt, erase ECM DTCs.
Perform several engine run cycles, turning the ignition off for at least 20 seconds
between each engine run cycle.
With the DRBIIIt, read the ECM DTCs.
Did this DTC set again?All
Ye s!Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Test Complete.
6WARNING: 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.
81
DRIVEABILITY - DIESEL
P1482-GLOW PLUG MODULE - COMMUNICATION ERROR ÐContinued
Symptom:
P1610-ENGINE CONTROL RELAY PLAUSIBILITY
When Monitored and Set Condition:
P1610-ENGINE CONTROL RELAY PLAUSIBILITY
When Monitored: During after-run.
Set Condition: The internal ECM timer determines that the Engine Control Relay
remains on for more than 2.0 seconds after the ECM has turned off the Engine Control
Relay.
POSSIBLE CAUSES
CHECK FOR OTHER DTCS
CHECK THE ECM POWER AND GROUNDS
ENGINE CONTROL MODULE
INTERMITTENT CONDITION
SUBSTITUTE ENGINE CONTROL RELAY
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, check for additional DTCs.
Are other DTCs present?All
Ye s!Refer to the Symptom List for diagnosis of the other DTCs before
continuing.
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.
Perform several ignition key cycles, pausing for at least 10 seconds between each
cycle.
Turn the ignition on.
With the DRB, read ECM DTCs.
Did this DTC set again?All
Ye s!Go To 3
No!Go To 5
87
DRIVEABILITY - DIESEL