
read opposite switch states.Note: The BS and
BLS are in the same switch housing.
BRAKE LAMP SWITCH (BLS):This switch pre-
pares the CAB for a possible antilock event. The
CAB uses an output state voltage from the BLS
when the brake pedal is either depressed/released.
The Fused Ignition Switch Output circuit supplies
12 volts to the BLS. A depressed brake pedal will
close the BLS circuit and the BLS Output circuit
supplies 12 volts at the CAB. When the driver
releases the brake pedal, the BLS Output circuit
voltage drops to 0 volts and the CAB senses the
brake pedal state. This tells the CAB what position
the brake pedal is currently in to make an ABS
event possible. When using the DRBIIItin Inputs/
Outputs, the BS and BLS will read opposite switch
states.Note: The BS and BLS are in the same
switch housing.
TRACTION CONTROL SYSTEM SWITCH
(TCSS):This switch signals the CAB to either turn
ON or OFF the TCS. The driver can toggle the
TCSS, which receives 12 volts from the D (+) Relay
Output circuit. Depending on the position of the
TCSS, open or closed, the CAB receives the TCSS
state voltage on the TCS Switch Sense circuit.
When 12 volts are applied to the TCS Switch Sense
circuit, the TCS is OFF. When no voltage is present,
the TCS is ON.
WHEEL SPEED SENSORS AND TONE
WHEELS:The Bosch 5.7 system uses one passive
WSS on each wheel. The sensor measures the wheel
speed by monitoring a rotating tone wheel. As the
teeth of the tone wheel move through the magnetic
field of the sensor an AC voltage and amperage is
generated. This signal frequency increases or de-
creases proportionally to the speed of the wheel.
The CAB monitors this signal to check for a sudden
change in single or multiple wheel decelerations. If
the deceleration of one or more wheels is not within
a predetermined amount, the CAB takes control for
antilock action through the HCU. Each WSS has a
magnetic inductive pick up coil (WSS) that is
mounted to a fixed component. There is an air gap
between the tone wheel and the speed sensor as-
sembly. Diagnostically, the coils of the Wheel Speed
Sensors have the same amount of resistance. When
measured across the CAB harness connector termi-
nals, the resistance should be between 1100 - 1800
ohms. Refer to service manual for WSS replacement
and air gap specifications.
Correct ABS operation is dependent on Tone
Wheel speed signal from the WSS. The vehicle
wheels and tires should all be the same size and
type to get accurate signals. In addition, all tires
should be at recommended tire pressures.3.7.5 SELF TESTS
The system software includes several self tests
that are performed every time the ignition is turned
on and the vehicle is driven. Some of the self tests
occur immediately, while others occur under normal
driving conditions while not in antilock operation.
The CAB checks continuously for a missing or
erratic WSS signals/circuits, tone wheels, solenoids,
pump motor or solenoid relay by performing several
tests such as: dynamic, static, ohmic, voltage drop,
and timed response. If any component exhibits a
fault during testing, the CAB will request to illumi-
nate the ABS and TCS warning indicators.
As an additional check of the ESP system, a road
test procedure is available on the DRBIIIt. This
test should be carried out when any ESP component
is replaced in order to ensure proper function. Since
the wheel speed sensors are required inputs to the
ESP, this test should also be performed if the wheel
speed sensors are replaced.
First, the brakes are applied with the vehicle
stationary. Then, the vehicle is driven at approxi-
mately 6 MPH. The driver has to make left and
right turns, with a minimum 90 degree steering
turning angle. If the indicator lamp goes out, every-
thing is in order. If the lamp remains illuminated,
the DRBIIItwill display the fault codes that are
causing the test to fail. The road test function is set
in the ESP control module, and can only be deacti-
vated once there are no more fault codes detected.
The Steering Angle Sensor must be initialized. A
procedure is carried out using the DRBIIItto
ensure that the module detects the exact position of
the sensor. The sensor must be calibrated any time
wheel alignment is changed, the steering column is
removed and re-installed, or the sensor is replaced.
3.8 USING THE DRBIIIT
Refer to the DRBIIItuser 's guide for instructions
and assistance with reading diagnostic trouble
codes, erasing diagnostic trouble codes and other
DRBIIItfunctions.
3.9 DRBIIITERROR MESSAGES
Under normal operation, the DRBIIItwill dis-
play one of only two error messages:
Ð User-Requested WARM Boot or User-Requested
COLD Boot.
If the DRBIIItshould display any other error
message, record the entire display and call the
STAR Center for information and assistance. This
is a sample of such an error message display:
4
GENERAL INFORMATION

4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRBIIITMULTIMETER IS DANGEROUS. IT
CAN EXPOSE YOU TO SERIOUS OR
POSSIBLE FATAL INJURY. CAREFULLY
READ AND UNDERSTAND THE CAUTIONS
AND THE SPECIFICATION LIMITS.
²Follow the vehicle manufacturer 's service speci-
fications at all times.
²Do not use the DRBIIItif it has been damaged.
²Do not use the test leads if the insulation is
damaged or if metal is exposed.
²To avoid electrical shock, do not touch the test
leads, tips, or the circuit being tested.
²Choose the proper range and function for the
measurement. Do not try voltage or current mea-
surements that may exceed the rated capacity.
²Do not exceed the limits shown in the table below:
FUNCTION INPUT LIMIT
Volts 0 - 500 peak volts AC
0 - 500 volts DC
Ohms (resistance)* 0 - 1.12 megaohms
Frequency Measured
Frequency Generated0-10kHz
Temperature -58 - +1100ÉF
-50 - +600ÉC
* Ohms cannot be measured if voltage is present.
Ohms can be measured only in a non-powered
circuit.
± Voltage between any terminal and ground
must not exceed 500v DC or 500v peak AC.
± Use caution when measuring voltage above
25v DC or 25v AC.
± Use the low current shunt to measure circuits
up to 10A. Use the high current clamp to
measure circuits exceeding 10A.
± When testing for the presence of voltage or
current, make sure the meter is functioning
correctly. Take a reading of a known voltage or
current before accepting a zero reading.
± When measuring current, connect the meter in
series with test load.
± When using the meter function, keep the
DRBIIItaway from spark plug or coil wires to
avoid measuring error from outside interfer-
ence.
4.3 WARNING
4.3.1 VEHICLE DAMAGE WARNINGS
Before disconnecting any control module, make
sure the ignition is ``off ''. Failure to do so could
damage the module.
When testing voltage or continuity at any control
module, use the terminal side (not the wire end) of
the connector. Do not probe a wire through the
insulation; this will damage it and eventually cause
it to fail because of corrosion.
Be careful when performing electrical tests so as
to prevent accidental shorting of terminals. Such
mistakes can damage fuses or components. Also, a
second code could be set, making diagnosis of the
original problem more difficult.
4.3.2 ROAD TESTING A COMPLAINT
VEHICLE
Some complaints will require a test drive as part
of the repair verification procedure. The purpose of
the test drive is to try to duplicate the diagnostic
code or symptom condition.
CAUTION: Before road testing a vehicle, be
sure that all components are reassembled.
During the test drive, do not try to read the
DRBIIITscreen while in motion. Do not hang
the DRBIIITfrom the rear view mirror or
operate it yourself. Have an assistant
available to operate the DRBIIIT.
4.4 DIAGNOSIS
1. Your diagnostic test procedure must begin with a
thorough visual inspection of the system in ques-
tion for damaged components or disconnected
connectors. For ABS, the brake lamps must be
operational prior to continuing.
2. Connect the DRBIIItto the data link connector
located under the dash. If the DRBIIItdoes not
power up, check the power and ground supplies
to the connector.
3. Select the system in question. Turn the ignition
on. If the DRBIIItdisplays ``No Responseº, refer
to Communication in the Body Diagnostic Pro-
cedures manual to diagnose the symptom.
4. Read and record all diagnostic trouble codes. If
any additional codes are present, proceed to the
appropriate test.
5. For ABS, if there are no diagnostic trouble codes
present, select ``Inputs/Outputs'' and read the
Brake Switch and Brake Lamp Switch inputs as
you press and release the brake pedal. If the
6
GENERAL INFORMATION

TABLE OF CONTENTS - Continued
*CHECKING THE FUEL PRESSURE SOLENOID CIRCUITS...................233
*CHECKING THE FUEL QUANTITY SOLENOID CIRCUITS....................234
*CHECKING THE POWER AND GROUNDS................................235
*ENGINE CRANKS BUT WILL NOT START.................................239
*ENGINE WILL NOT CRANK.............................................242
VERIFICATION TESTS
VERIFICATION TESTS..................................................246
8.0 COMPONENT LOCATIONS..............................................249
8.1CONTROL MODULES.............................................249
8.2CONTROLS AND SOLENOIDS......................................249
8.3DATA LINK CONNECTOR..........................................250
8.4SENSORS.......................................................251
8.5SWITCHES......................................................253
9.0 CONNECTOR PINOUTS................................................255
ACCELERATOR PEDAL POSITION SENSOR (OBD).........................255
AIRBAG CONTROL MODULE - YELLOW...................................255
BOOST PRESSURE SENSOR (OBD)......................................255
BOOST PRESSURE SERVOMOTOR (OBD)................................256
CAMSHAFT POSITION SENSOR - BLACK.................................256
CONTROLLER ANTILOCK BRAKE........................................257
CRANKCASE HEATER - BLACK..........................................257
CRANKSHAFT POSITION SENSOR - BLACK...............................258
DATA LINK CONNECTOR - BLACK........................................258
EGR VALVE - BLACK...................................................258
ENGINE CONTROL MODULE C1 (OBD)...................................259
ENGINE CONTROL MODULE C2 (OBD)...................................260
ENGINE COOLANT TEMPERATURE SENSOR - BLACK......................260
ENGINE OIL SENSOR - BLACK..........................................261
FUEL INJECTOR NO. 1 - BLACK.........................................261
FUEL INJECTOR NO. 2 - BLACK.........................................261
FUEL INJECTOR NO. 3 - BLACK.........................................261
FUEL INJECTOR NO. 4 - BLACK.........................................262
FUEL INJECTOR NO. 5 - BLACK.........................................262
FUEL PRESSURE SENSOR - BLACK.....................................262
FUEL PRESSURE SOLENOID............................................262
FUEL PUMP (OBD).....................................................262
FUEL PUMP RELAY (OBD)..............................................263
FUEL QUANTITY CONTROL VALVE (OBD).................................263
FUEL TEMPERATURE SENSOR..........................................263
ENGINE CONTROL RELAY (FUSE BLOCK NO. 1)...........................265
FUSES (FUSE BLOCK NO. 1)............................................265
FUSES (FUSE BLOCK NO. 2)............................................267
FUSES (FUSE/RELAY BLOCK)...........................................269
STARTER MOTOR RELAY (FUSE/RELAY BLOCK)...........................269
GLOW PLUG CONTROL MODULE C1 - BLACK.............................270
GLOW PLUG CONTROL MODULE C2 - BLACK.............................270
INTAKE AIR PRESSURE SENSOR (OBD)..................................270
INTAKE AIR TEMPERATURE SENSOR - BLACK............................270
x

3.2.6 SKREEM OPERATION
When ignition power is supplied to the SKREEM,
the SKREEM performs an internal self-test. After
the self-test is complete, the SKREEM energizes
the antenna (this activates the transponder chip)
and sends a challenge to the transponder chip. The
transponder chip responds to the challenge by gen-
erating an encrypted response message.
After responding to the coded message, the tran-
sponder sends a transponder ID message to the
SKREEM. The SKREEM compares the transpon-
der ID message to the available valid key codes in
SKREEM memory (8 key maximum at any one
time). After validating the ignition key the
SKREEM sends a CAN Bus message request to the
ECM, then waits for the ECM response. If the ECM
does not respond, the SKREEM will send the re-
quest again. If the ECM does not respond again, the
SKREEM will stop sending the request and store a
trouble code in memory. If the ECM sends a correct
response to the SKREEM, the SKREEM sends a
valid/invalid key message to the ECM. The ECM
will allow or disallow engine operation based on this
message.
Secret Key - an electronically stored value (iden-
tification number) that is unique to each SKREEM.
The secret key is stored in the SKREEM, ECM and
all ignition key transponders.
Challenge - a random number that is generated by
the SKREEM at each ignition key cycle.
The secret key and challenge are the two vari-
ables used in the algorithm that produces the
encrypted response message. The transponder uses
the crypto algorithm to receive, decode and respond
to the message sent by the SKREEM. After re-
sponding to the coded message, the transponder
sends a transponder ID message to the SKREEM.
3.3 DIAGNOSTIC TROUBLE CODES
Each diagnostic trouble code (DTC) is diagnosed
by following a specific procedure. The diagnostic
test procedure contains step-by-step instruction for
determining the cause of the DTC as well as no
trouble code problems. It is not necessary to per-
form all of the tests in this book to diagnose an
individual code.
Always begin diagnosis by reading the DTCs
using the DRBIIIt. This will direct you to the
specific test(s) that must be performed.
3.3.1 HARD CODE
A DTC that comes back within one cycle of the
ignition key is a hard code. This means that the
problem is current every time the ECM/SKREEM
checks that circuit or function. Procedures in this
manual verify if the DTC is a hard code at thebeginning of each test. When the fault is not a hard
code, an intermittent test must be performed.
NOTE: If the DRBIIITdisplays faults for
multiple components (i.e. ECT, MAF, IAT
sensors) identify and check the shared
circuits for possible problems before
continuing (i.e. sensor grounds or 5-volt
supply circuits). Refer to the appropriate
schematic to identify shared circuits.
3.3.2 INTERMITTENT CODE
A DTC that is not current every time the ECM/
SKREEM checks the circuit or function is an inter-
mittent code. Most intermittent DTCs are caused
by wiring or connector problems. Problems that
come and go like this are the most difficult to
diagnose; they must be looked for under specific
conditions that cause them. The following checks
may assist you in identifying a possible intermit-
tent problem.
± Visually inspect the related wire harness con-
nectors. Look for broken, bent, pushed out or
corroded terminals.
± Visually inspect the related wire harness.
Look for chafed, pierced or partially broken
wire.
± Refer to hotlines or technical service bulletins
that may apply.
NOTE: Electromagnetic (radio) interference
can cause an intermittent system
malfunction. This interference can interrupt
communication between the ignition key
transponder and the SKREEM.
3.3.3 ECM DIAGNOSTIC TROUBLE CODES
IMPORTANT NOTE: Before replacing the
ECM for a failed driver, control circuit or
ground circuit, be sure to check the related
component/circuit integrity for failures not
detected due to a double fault in the circuit.
Most ECM driver/control circuit failures are
caused by internal failures to components
(i.e. relays and solenoids) and shorted
circuits (i.e. sensor pull-ups, drivers and
ground circuits). These faults are difficult to
detect when a double fault has occurred and
only one DTC has set.
If the DRBIIItdisplays faults for multiple com-
ponents (i.e. MAF, ECT, ENG OIL, etc.), identify
and check the shared circuits for possible problems
before continuing (i.e. sensor grounds or 5-volt
3
GENERAL INFORMATION

ohmmeter
voltmeter
jumper wires and probes
oscilloscope
6.0 GLOSSARY OF TERMS
A/Cair conditioning
APPaccelerator pedal position (sensor)
BCMbody control module
BPboost pressure (sensor)
CKPcrankshaft position (sensor)
CMPcamshaft position (sensor)
CTMcentral timer module
DLCdata link connector
ECMengine control module
ECTengine coolant temperature (sensor)
EGRexhaust gas recirculation (solenoid/
valve)
EOSengine oil sensor
IATintake air temperature (sensor)
IPintake pressure sensorMAFmass air flow (sensor)
MILmalfunction indicator lamp
msmillisecond(s)
O2oxygen sensor
PDCpower distribution center
S/Cspeed control
SKREEMsentry key remote entry module
SRCsignal range check
WIFwater in fuel (sensor)
10
GENERAL INFORMATION

Symptom List:
P0105-INTAKE PRESSURE SENSOR CAN MESSAGE ERROR
P0105-INTAKE PRESSURE SENSOR PLAUSIBILITY
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P0105-INTAKE PRESSURE
SENSOR CAN MESSAGE ERROR.
POSSIBLE CAUSES
AIR FILTER
AIR RESTRICTION
INTERMITTENT CONDITION
CAN BUS COMMUNICATION DTCS
HIGH RESISTANCE IN THE INTAKE PRESSURE SENSOR SIGNAL CIRCUIT
HIGH RESISTANCE IN THE INTAKE PRESSURE SENSOR GROUND CIRCUIT
CAN BUS CIRCUITS OPEN TO THE SHIFTER MODULE
HIGH RESISTANCE IN THE INTAKE PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT
ENGINE CONTROL MODULE
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: 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, wait 30 seconds.
Test drive the vehicle.
With the DRB, read ECM DTCs.
Did this DTC set again?All
Ye s!Go To 2
No!Go To 9
2 Turn the ignition off.
Remove and inspect the Air Filter for soiling or excessive dirt and debris which may
cause air flow restriction.
Were any of these problems found?All
Ye s!Replace the Air Filter element.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 3
25
DRIVEABILITY - DIESEL

Symptom:
P0115-ENGINE COOLANT TEMP SENSOR CIRCUIT PLAUSIBILITY
WITH ENGINE OIL SENSOR
When Monitored and Set Condition:
P0115-ENGINE COOLANT TEMP SENSOR CIRCUIT PLAUSIBILITY WITH EN-
GINE OIL SENSOR
When Monitored: With the engine running.
Set Condition: The ECT Sensor signal indicates a different engine temperature than the
EOS Sensor.
POSSIBLE CAUSES
CURRENT DTC
ECT SENSOR
ECT SENSOR - COLD
ECT SENSOR - HOT
ENGINE OIL SENSOR SENSOR
HGH RESISTANCE IN ECT SENSOR CIRCUITS
ENGINE COLD TOO LONG
TEST ACTION APPLICABILITY
1 Verify that the coolant level is correct.
Start the engine.
NOTE: The thermostat must be operating correctly for this test to be valid.
With the DRBIIIt, erase ECM DTCs.
With the DRBIIIt, set the engine RPM to 1500 and allow the engine to warm up for
10-15 minutes.
With the DRBIIIt, monitor the Engine Coolant Temperature value during the warm
up cycle. Make sure the transition of temperature change is smooth.
Did the engine temperature reach a minimum of 80É C (176É F)?All
Ye s!Go To 2
No!Refer to the Service Information for cooling system performance
diagnosis. The most probable cause is a Thermostat problem.
Also, refer to any related TSBs.
Perform ROAD TEST VERIFICATION - VER-2.
2 Turn the ignition on.
With the DRBIIIt, read the ECM DTCs.
Did this DTC return after performing the previous test?All
Ye s!Go To 3
No!Check for possible connecor or wiring problems at the ECT sensor
that may cause an intermittent problem. Repair as necessary.
Test Complete.
Perform ROAD TEST VERIFICATION - VER-2.
42
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: 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: The engine oil must be at the proper level for this test to be valid.
Refer to the Service Information and ensure the engine oil level is at the
specified level.
Turn the ignition on.
With the DRB, erase ECM DTCs.
Start the engine several times, letting the engine run for at least 30 seconds at a
time.
With the DRB, read ECM DTCs.
Did this DTC set again?All
Ye s!Go To 2
No!Go To 10
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.
Refer to any Technical Service Bulletins (TSB) that may apply.
Turn the ignition off.
NOTE: This DTC implies that the engine may be contaminated by water,
engine coolant or other material due to a mechanical or service failures
such as failed gaskets, seals, cracks or incorrectly installed components.
Inspect the engine for conditions referred to in the above note.
Were any of the above conditions present?All
Ye s!Repair as necessary.
Perform ROAD TEST VERIFICATION - VER-2.
No!Go To 3
3 Turn the ignition off.
Disconnect the Engine Oil Sensor harness connector.
Turn the ignition on.
Measure the voltage of the Engine Oil 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 7
11 4
DRIVEABILITY - DIESEL
P2014-ENGINE OIL SENSOR OIL TEMPERATURE PLAUSIBILITY Ð
Continued