Chrysler PT Cruiser 2001 Service Manual Supplement page 2472

GENERAL INFORMATION
•
Use caution when measuring voltage above 25v
DC or 25v AC.
• The circuit being tested must be protected by a
10A fuse or circuit breaker.
• 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 cur-
rent, make sure the meter is functioning cor-
rectly. Take a reading of a known voltage or
current before accepting a zero reading.
• When measuring current, connect the meter in
series with the load.
• Disconnect the live test lead before disconnecting
the common test lead.
•
When using the meter function, keep the
DRBIII away from spark plug or coil wires to
avoid measuring 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
VEHICLE, BE
COMPONENTS ARE
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRB SCREEN WHILE IN MOTION.
DO NOT HANG THE DRB FROM THE REAR
VIEW MIRROR OR OPERATE IT YOURSELF.
HAVE AN ASSISTANT
OPERATE THE DRB.
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.
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.
ROAD TESTING
SURE THAT ALL
REASSEMBLED.
AVAILABLE
5.0 RECOMMENDED TOOLS
AND EQUIPMENT
DRBIII (diagnostic read-out box) scan tool
fuel pressure adapter (C-6631) or #6539
fuel pressure kit (C-4799-B) or #5069
fuel release hose (C-4799-1)
Min Air flow fitting #6457
jumper wires
ohmmeter
oscilloscope
vacuum gauge
voltmeter
12 volt test light minimum 25 ohms resistance
with probe #6801
CAUTION: A 12 VOLT TEST LIGHT SHOULD
NOT BE USED FOR THE FOLLOWING
CIRCUITS, DAMAGE TO THE POWERTRAIN
CONTROLLER WILL OCCUR.
• 5 Volt Supply
• 8 Volt Supply
•
J1850 PCI Bus
•
CCD Bus
• CKP Sensor Signal
• CMP Sensor Signal
•
Vehicle Speed Sensor Signal
•
O2 Sensor Signal
A
6.0 GLOSSARY OF TERMS
ABS antilock brake system
backfire, fuel ignites in either the intake or
popback the exhaust system
TO
CKP crank position sensor
CMP camshaft position sensor
cuts out, a steady pulsation or the inability of
misses the engine to maintain a consistent
rpm
DLC data link connector (previously
called engine diagnostic connector)
detona- a mild to severe ping, especially un-
tion, der loaded engine conditions
spark
knock
ECT engine coolant temperature sensor
EGR exhaust gas recirculation valve and
system
genera- previously called alternator
tor
12