Page 505 of 2305

Symptom List:
P1482-GLOW PLUG MODULE - EXCESS CURRENT
P2133-GLOW PLUG #1 CIRCUIT EXCESSIVE CURRENT
P2133-GLOW PLUG #1 CIRCUIT OPEN CIRCUIT
P2133-GLOW PLUG #1 CIRCUIT SHORT TO GROUND
P2133-GLOW PLUG #1 CIRCUIT SHORT TO VOLTAGE
P2134-GLOW PLUG #2 CIRCUIT EXCESSIVE CURRENT
P2134-GLOW PLUG #2 CIRCUIT OPEN CIRCUIT
P2134-GLOW PLUG #2 CIRCUIT SHORT TO GROUND
P2134-GLOW PLUG #2 CIRCUIT SHORT TO VOLTAGE
P2135-GLOW PLUG #3 CIRCUIT EXCESSIVE CURRENT
P2135-GLOW PLUG #3 CIRCUIT OPEN CIRCUIT
P2135-GLOW PLUG #3 CIRCUIT SHORT TO GROUND
P2135-GLOW PLUG #3 CIRCUIT SHORT TO VOLTAGE
P2136-GLOW PLUG #4 CIRCUIT EXCESSIVE CURRENT
P2136-GLOW PLUG #4 CIRCUIT OPEN CIRCUIT
P2136-GLOW PLUG #4 CIRCUIT SHORT TO GROUND
P2136-GLOW PLUG #4 CIRCUIT SHORT TO VOLTAGE
P2137-GLOW PLUG #5 CIRCUIT EXCESSIVE CURRENT
P2137-GLOW PLUG #5 CIRCUIT OPEN CIRCUIT
P2137-GLOW PLUG #5 CIRCUIT SHORT TO GROUND
P2137-GLOW PLUG #5 CIRCUIT SHORT TO VOLTAGE
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P1482-GLOW PLUG MODULE -
EXCESS CURRENT.
POSSIBLE CAUSES
GLOW PLUG
GLOW PLUG CONTROL CIRCUIT OPEN
GLOW PLUG CONTROL CIRCUIT SHORTED TO GROUND
GLOW PLUG CONTROL CIRCUIT SHORTED TO VOLTAGE
GLOW PLUG MODULE
INTERMITTENT CONDITION
82
DRIVEABILITY - DIESEL
Page 506 of 2305

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 DRB, erase ECM DTCs.
Perform several ignition cycles leaving the ignition on for at least 10 seconds then off
for 10 seconds.
With the DRBIIIt, read the ECM DTCs.
Did this DTC set again?All
Ye s!Go To 2
No!Go To 6
2 Turn the ignition off.
Disconnect each Glow Plug harness connector.
Disconnect the Glow Plug Module harness connector.
Measure the resistance of each Glow Plug Control circuit.
Is the resistance below 10.0 ohms for each circuit?All
Ye s!Go To 3
No!Repair the appropriate Glow Plug Control circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
3 Turn the ignition off.
Disconnect each Glow Plug harness connector.
Disconnect the Glow Plug Module harness connector.
Measure the resistance between ground and each Glow Plug Control circuit.
Is the resistance below 1000.0 ohms for any of the measurements?All
Ye s!Repair the appropriate Glow Plug Control circuit for a short to
ground.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 4
4 Turn the ignition off.
Disconnect each Glow Plug harness connector.
Disconnect the Glow Plug Module harness connector.
Turn the ignition on.
Measure the voltage of each Glow Plug Control circuit.
Is the voltage below 1.0 volt for each circuit?All
Ye s!Go To 5
No!Repair the appropriate Glow Plug Control circuit for a short to
voltage
Perform ROAD TEST VERIFICATION - VER-2.
83
DRIVEABILITY - DIESEL
P1482-GLOW PLUG MODULE - EXCESS CURRENT ÐContinued
Page 507 of 2305

TEST ACTION APPLICABILITY
5 Turn the ignition off.
With the DRBIIIt, erase ECM DTCs.
Refer to the Service Information and perform the Glow Plug Test on each Glow plug.
Did each Glow Plug pass the test?All
Ye s!Replace the Glow Plug Module.
Perform ROAD TEST VERIFICATION - VER-2.
No!Replace the appropriate Glow Plug in accordance with the Service
Information.
Perform ROAD TEST VERIFICATION - VER-2.
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.
84
DRIVEABILITY - DIESEL
P1482-GLOW PLUG MODULE - EXCESS CURRENT ÐContinued
Page 508 of 2305

Symptom List:
P1482-GLOW PLUG MODULE - INCORRECT TIMER
P1482-GLOW PLUG MODULE - INTERNAL FAULT
P2538-GLOW PLUG MODULE COMMUNICATION ERROR
P2538-GLOW PLUG MODULE EXCESSIVE CURRENT ERROR
P2538-GLOW PLUG MODULE TIMER ERROR
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P1482-GLOW PLUG MODULE -
INCORRECT TIMER.
POSSIBLE CAUSES
GLOW PLUG MODULE
INTERMITTENT CONDITION
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.
NOTE: This DTC indicates an internal Glow Plug Control Module problem
or an incorrect Glow Plug Module has been installed.
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 Glow Plug Control Module in accor-
dance with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 2
85
DRIVEABILITY - DIESEL
Page 509 of 2305

TEST ACTION APPLICABILITY
2WARNING: 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.
86
DRIVEABILITY - DIESEL
P1482-GLOW PLUG MODULE - INCORRECT TIMER ÐContinued
Page 510 of 2305

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
Page 511 of 2305

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Install a substitute relay in place of the Engine Control Relay.
Turn the ignition on.
With the DRBIIIt, erase 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 4
No!Replace the Engine Control Relay.
Perform ROAD TEST VERIFICATION - VER-2.
4 Refer to symptom Checking the ECM Power and Grounds.
Are the ECM Power and Ground circuits o.k.?All
Ye s!Replace the ECM in accordance with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
No!Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
5WARNING: 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.
88
DRIVEABILITY - DIESEL
P1610-ENGINE CONTROL RELAY PLAUSIBILITY ÐContinued
Page 512 of 2305

Symptom:
P1610-ENGINE CONTROL RELAY SHUTS OFF TOO EARLY
When Monitored and Set Condition:
P1610-ENGINE CONTROL RELAY SHUTS OFF TOO EARLY
When Monitored: During after-run.
Set Condition: The internal ECM timer determines that the Engine Control Relay has
shut off before the AFTER-RUN mode of operation has been completed.
POSSIBLE CAUSES
CHECK FOR OTHER DTCS
INTERMITTENT CONDITION
SUBSTITUTE ENGINE CONTROL RELAY
ENGINE CONTROL RELAY CONTROL CIRCUIT OPEN INTERMITTENTLY
ENGINE CONTROL MODULE
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
89
DRIVEABILITY - DIESEL