important to block the wheels on front-wheel drive
vehicles; the parking brake does not hold the drive
wheels.
When servicing a vehicle, always wear eye pro-
tection, and remove any metal jewelry such as
watchbands or bracelets that might make an inad-
vertent electrical contact.
When diagnosing a powertrain system problem,
it is important to follow approved procedures where
applicable. These procedures can be found in ser-
vice manual procedures. Following these proce-
dures is very important to the safety of individuals
performing diagnostic tests.
4.2.2 VEHICLE PREPARATION FOR
TESTING
Make sure the vehicle being tested has a fully
charged battery. If it does not, false diagnostic codes
or error messages may occur.
4.2.3 SERVICING SUB ASSEMBLIES
Some components of the powertrain system are
intended to be serviced in assembly only. Attempt-
ing to remove or repair certain system sub-
components may result in personal injury and/or
improper system operation. Only those components
with approved repair and installation procedures in
the service manual should be serviced.
4.2.4 DRBIIITSAFETY INFORMATION
WARNING: EXCEEDING THE LIMITS OF THE
DRB MULTIMETER IS DANGEROUS. IT CAN
EXPOSE YOU TO SERIOUS INJURY.
CAREFULLY READ AND UNDERSTAND THE
CAUTIONS AND THE SPECIFICATION
LIMITS.
Follow the vehicle manufacturer 's service specifi-
cations at all times.
²Do not use the DRB if 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 megohms
FUNCTION INPUT LIMIT
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.
²Voltage between any terminal and ground must
not exceed 500v DC or 500v peak AC.
²Use caution when measuring voltage above 25v
DC or 25v AC.
²The circuit being tested must be protected by a
10A fuse or circuit breaker.
²Use the low current shunt to measure circuits up
to 10A. Use the high current clamp to measure
circuits exceeding 10A.
²When testing for the presence of voltage or cur-
rent, make sure the meter is functioning cor-
rectly. Take a reading of a known voltage or
current before accepting a zero reading.
²When measuring current, connect the meter in
series with the load.
²Disconnect the live test lead before disconnecting
the common test lead.
²When using the meter function, keep the DRBIIIt
away from spark plug or coil wires to avoid mea-
suring error from outside interference.
4.3 WARNINGS AND CAUTIONS
4.3.1 ROAD TEST WARNINGS
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.
4.3.2 VEHICLE DAMAGE CAUTIONS
Before disconnecting any control module, make
sure the ignition is off. Failure to do so could
damage the module.
11
GENERAL INFORMATION
4.3 WARNINGS
4.3.1 VEHICLE DAMAGE WARNINGS
Before disconnecting any control module, make
sure the ignition is ªoffº. 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 TEST 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.
Road testing is an essential step in the diagnostic
process that must not be overlooked. Along with
diagnostic information obtained from the DRBIIIt
Scan Tool and the original customer concern, the
road test helps to verify the problem and observe
operation under actual vehicle driving conditions.
Just as important as the road test is, there are
preliminary inspections that should be carried out
prior to the road test. Always check the fluid level
and condition before going on a road test or per-
forming other tests. Also try to determine the type
of fluid being used. Improper fluid can result in
problems. Additionally, a variety of complaints can
be caused by incorrect fluid level. Some of the
conditions caused by incorrect fluid level are as
follows:
²Delayed engagement
²Poor shifting or erratic shifts
²Excessive noise
²Overheating
The next step is to verify that the shift linkage is
correctly adjusted. If the gearshift linkage is incor-rectly adjusted because of wear or incorrect adjust-
ment, a number of complaints can result.
The TCM monitors the Shift Lever Position (SLP)
Sensor at all times. If the linkage is incorrectly
adjusted, the TCM may sense a shift lever position
that is not correct for the gear range chosen by the
driver. This may cause diagnostic trouble codes to
be set and a possible limp-in situation.
The following complaints may also be the result
of an incorrectly adjusted or worn linkage.
²Delayed clutch engagement or erratic shifts
²Vehicle able to drive in Neutral
²Engine not able to crank in Park or Neutral
²Gearshift linkage able to be shifted without the
key in the ignition
²Not able to remove the ignition key in Reverse
²Parking pawl not engaging
The shift linkage should also be adjusted when
replacing the transaxle, repairing the valve body or
repairing any component between the shift lever
and the transaxle.
Some questions to ask yourself when considering
the road test are listed below:
²Is the complaint or concern what you think it is,
based the driver 's description of the problem?
²Is the transaxle operating normally, or is there a
real problem?
²When does the malfunction occur?
²Is the problem in only one gear range?
²What temperature does the complaint occur?
²Is the transaxle in limp-in mode?
4.3.3 ELECTRONIC PINION FACTOR
WARNINGS
The pinion factor must be set for all new trans-
mission control modules. If the pinion factor is not
set or if it is set incorrectly, any speedometer, speed
control, rolling door locks, and other devices that
are operated by the powertrain and body controllers
will not function properly.
4.3.4 BULLETINS AND RECALLS
The service procedures contained in this manual
are correct. provided that all applicable Safety
Recalls and Technical Service Bulletins have been
performed.
5.0 REQUIRED TOOLS AND
EQUIPMENT
> DRBIIIt(diagnostic read-out box) - Must be at
latest release level.
20
GENERAL INFORMATION
