
SEAT BELT TENSIONER-DRIVER - YELLOWCAV CIRCUIT FUNCTION
1 20BL DRIVER SEAT BELT TENSIONER LINE 2
2 20BR/YL DRIVER SEAT BELT TENSIONER LINE 1
SEAT BELT TENSIONER-PASSENGER - YELLOWCAV CIRCUIT FUNCTION
1 20BL PASSENGER SEAT BELT TENSIONER LINE 2
2 20BR PASSENGER SEAT BELT TENSIONER LINE 1
SECURITY SYSTEM MODULE C1 - BROWNCAV CIRCUIT FUNCTION
1 16BK/WT LEFT TURN SIGNAL
2- -
3- -
4 16BK/DG RIGHT TURN SIGNAL
5 16BK/VT FAN STAGE 1 RELAY
6 16WT/RD WARM AIR AUXILIARY HEATER CONTROL
7 16RD/GY FUSED B(+)
8 16BK/GY FUSED OPTIONAL EQUIPMENT RELAY OUTPUT
9 18VT/DG TOWING/INTRUSION SENSOR INDICATOR DRIVER
10 - -
11 16BR/YL FRONT COURTESY LAMPS CONTROL
12 16BR/WT DOOR AJAR SWITCH SENSE
13 16RD/DG FUSED B(+)
14 16BK/BL HOOD AJAR SWITCH SENSE
15 18GY/WT PANIC SWITCH SENSE
16 16BR GROUND
17 18GY/BR TOWING SENSOR SWITCH SENSE
18 18GY/YL INTRUSION SENSOR SWITCH SENSE
19 - -
20 16BK DRIVER CYLINDER UNLOCK SENSE
21 16RD DRIVER CYLINDER LOCK SENSEC
O
N
N
E
C
T
O
R
P
I
N
O
U
T
S
285
CONNECTOR PINOUTS

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the CAB harness connector.
Inspect the CAB/CAB harness connector for damage.
Is there any broken, bent, pushed out, corroded or spread terminals?All
Ye s!Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off.
Turn the ignition on.
With the DRBIIItin Sensors, read the Relay Output voltage.
Start the engine.
With the DRBIIItin Sensors, read the Relay Output voltage.
Select the Relay Output voltage that was displayed on the DRBIIIt.All
Voltage below 9.4 volts.
Go To 5
Voltage above 17.4 volts.
Go To 7
Voltage between 9.4 and 17.4 volts.
Go To 8
5 Turn the ignition off.
Disconnect the CAB harness connector.
Start the engine.
Allow the engine to idle.
WARNING: 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.
Measure the voltage of the Fused Optional Equipment Relay Output circuit in the
CAB harness connector.
Raise the engine speed above 2,000 RPM's.
Measure the voltage of the Fused Optional Equipment Relay Output circuit in the
CAB harness connector.
Is the voltage less than 9.4 volts?All
Ye s!Repair the Fused Optional Equipment Relay Output circuit for an
open.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 6
61
BRAKES (CAB)
RELAY OUTPUT VOLTAGE ÐContinued

TEST ACTION APPLICABILITY
6 Turn the ignition off.
Disconnect the CAB harness connector.
Start the engine.
Allow the engine to idle.
WARNING: 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.
Measure the voltage of both Fused B(+) circuits in the CAB harness connector.
Raise the engine speed above 2,000 RPM's.
Measure the voltage of both Fused B(+) circuits in the CAB harness connector.
Is the voltage below 9.4 volts?All
Ye s!Repair the Fused B(+) circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 7
7 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the voltage between the Fused B(+) circuit and both Ground circuits in the
CAB harness connector.
Is the voltage above 9.4 volts?All
Ye s!Repair any charging system related DTCs before continuing. If no
charging system or system voltage DTCs are present in any
module, replace the Controller Antilock Brake in accordance with
the Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No!Repair the Ground circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
8 Turn the ignition off.
Visually inspect the related wiring harness.
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out, or corroded terminals.
Ensure the battery is fully charged.
Inspect the vehicle for aftermarket accessories that may exceed the Generator
System output.
Were any problems found?All
Ye s!Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Test Complete.
62
BRAKES (CAB)
RELAY OUTPUT VOLTAGE ÐContinued

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: If there are other DTC's set with this DTC repair other DTC's before
continuing with this diagnostic procedure.
NOTE: This DTC indicates an internal ECM problem except in the case of
DTC P2352 where it may indicate a fuel injector problem. Using the Service
Information, check the fuel injectors for leakage before replacing the ECM.
NOTE: This code can be caused by an intermittent problem in the wiring
and connectors to the Engine Control Module. Inspect the Engine Control
Module harness connector and associated wiring for signs of poor terminal
contact.
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!Go To 2
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.
18
DRIVEABILITY - DIESEL
P-1105 ATMOSPHERIC PRESSURE SENSOR PLAUSIBILITY WITH
BOOST PRESSURE SENSOR Ð
Continued

TEST ACTION APPLICABILITY
15 Turn the ignition off.
Disconnect the MAF 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 MAF Sensor 5 Volt Supply circuit in the ECM harness
connector.
Is the voltage above 1.0 volt?All
Ye s!Repair the MAF 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.
16WARNING: 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.
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.
24
DRIVEABILITY - DIESEL
P0100-MASS AIR FLOW SENSOR SIGNAL VOLTAGE TOO LOW Ð
Continued

TEST ACTION APPLICABILITY
8 Turn the ignition off.
Disconnect the Intake Pressure Sensor harness connector.
Disconnect the ECM harness connectors.
Measure the resistance of the Intake Pressure Sensor 5-volt Supply circuit.
Is the resistance below 10.0 ohms?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 Intake Pressure Sensor 5 Volt Supply circuit for high
resistance.
Perform ROAD TEST VERIFICATION - VER-2.
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.
27
DRIVEABILITY - DIESEL
P0105-INTAKE PRESSURE SENSOR CAN MESSAGE ERROR ÐContinued

TEST ACTION APPLICABILITY
6 Turn the ignition off.
NOTE: Ensure all harness connectors are connected.
Turn the ignition on.
Measure the voltage of the Intake Pressure Sensor Signal circuit by back probing
ECM harness connector C2, cavity 11.
Is the voltage above 4.85 volts?All
Ye s!Replace the Intake Pressure Sensor.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 7
7 Turn the ignition on.
With the DRB, read ECM DTCs.
With the DRBIIIt, erase 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!Ensure good terminal contact between the Intake Pressure Sen-
sor harness connector and the sensor. The repair is complete.
Perform ROAD TEST VERIFICATION - VER-2.
8WARNING: 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.
30
DRIVEABILITY - DIESEL
P0105-INTAKE PRESSURE SENSOR SIGNAL VOLTAGE TOO HIGH Ð
Continued

TEST ACTION APPLICABILITY
8WARNING: 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.
33
DRIVEABILITY - DIESEL
P0105-INTAKE PRESSURE SENSOR SIGNAL VOLTAGE TOO LOW Ð
Continued