LW2 V6-3.0L VIN R (2000)
see if the customer has installed any non-factory installed items that could require constant voltage such as a cellular phone, anti-theft system, etc.
IMPORTANT: The ignition key must be removed from the cylinder before parasitic load testing. The keyminder circuit is activated by the key cylinder
switch when the key is in the ignition cylinder, which adds 20 milliamps of current draw.
In the following section "Parasitic Load Testing," two methods will be explained for testing a vehicle for parasitic loads. One method is with the Saturn
Parasitic Load Tester (SA 9130Z) and the other method is with a digital multimeter.
General Information
This group of settings on a multimeter allow you to accurately test for continuity and determine the resistance of many vehicle components.
Continuity
To check for continuity in a circuit use the lowest ohm scale available. Place the leads of the multimeter on each end of the circuit or component being
tested. A reading of less than one ohm indicates acceptable continuity.
Resistance
To test for resistance values, place the leads of the multimeter on each side of the circuit or component being tested. Adjust the ohm settings on the
multimeter until an acceptable reading is displayed. The lowest scale that gives a reading without going over the range (1 or OL) gives the most accurate
reading. Compare the reading displayed on the multimeter to the specification. Verify that the scale reading on the multimeter is the same as in the
specification (megohms, kilohms or ohms).
NOTE: When using a multimeter on the ohmmeter or diode test scale, make sure the circuit or component is disconnected from a power source.
Applying voltage to a multimeter when you are measuring resistance can damage the multimeter.
Diode Testing
Most digital multi meters have a Diode setting. This setting is used to test a diode to verify current flows in only one direction.
A good diode will display between 0.4 and 0.8 Volt on the meter when the leads are forward biasing the diode, this indicates the diode is allowing
current to flow in that direction. When the leads are reversed, the meter should read 1 or OL, indicating the diode is blocking the flow of current in the
opposite direction. This indicates a good diode. If the diode allows current flow in both directions or prevents current flow in both directions, the diode is
damaged and should be replaced.
Multimeter Display Reading
Diagnostic Service Probe
IMPORTANT:
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Diagnostic service probes are for use on 35, .50 and .80 mm (22, 20 and 18 gage) wires only.
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The diagnostic service probes must be left on the wire after use. The probe contains a sealant that will protect the wire from corrosion. Do not
remove the diagnostic service probe after use.
The use of the diagnostic service probe offers many advantages in system diagnostics over the old jumper wire and terminal back-probe methods. The
most important advantage of the diagnostic service probe method of diagnostics is the ability to observe the operation of a circuit without disturbing
the components or connections. This is an important advantage since many circuit failures are vibration or connection related. The diagnostic service
probe is designed to firmly hold multimeter test probes to allow more accurate readings while the circuit is operating. Circuits with bad connectors,
grounds, or components are easier to diagnose while they are operating.
Attach the diagnostic service probe to the wire leading to the connector and insert your multimeter into the diagnostic service probe. Put the meter on
the appropriate scale and observe the readings. If the readings do not compare with the expected readings, gently wiggle the wire back and forth in the
connector.
If the reading on the meter changes while you are wiggling the wire, the terminal or connector is faulty. Disconnect the connector and examine the
terminals and connector cavities for damage. Check the terminals to see if a known good terminal makes a firm connection. Do this by inserting a
known good male terminal into the female terminal you are testing. The male terminal should be held firmly in place by the female terminal and
should not be loose enough to fall out if the female terminal is held downward. Likewise, test a male terminal by inserting it into a known good female
terminal. The two terminals should fit snugly together and should not separate if the male terminal is held vertically downward. If the connections are
good (both wire connections and the connection to the component), check the ground connection. Attach a diagnostic service probe to the ground side
of the circuit or component. Place a multimeter probe in the diagnostic service probe and the other probe to a known good ground.
