Regal L4-2.0L Turbo (2011)
Cigarette Lighter: Diagnostic Aids
Inducing Intermittent Fault Conditions
Inducing Intermittent Fault Conditions
Special Tools
J-25070 - Heat Gun
For equivalent regional tools, refer to Special Tools (See: Power and Ground Distribution/Tools and Equipment).
Many intermittent open or shorted circuits are affected by harness/connector movement that is caused by vibration, engine torque, bumps/rough
pavement, etc. In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness if the malfunction appears to be
vibration related. Manipulation of a circuit can consist of a wide variety of actions, including:
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Wiggling the harness
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Disconnecting a connector and reconnecting
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Stressing the mechanical connection of a connector
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Pulling on the harness or wire in order to identify a separation/break inside the insulation
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Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool connected, wiggling the wires may uncover a faulty input to
the control module. The snapshot option would be appropriate here. Refer to Scan Tool Snapshot Procedure (See: Testing and Inspection/Component
Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure). Another option is, with the
component commanded ON and OFF by the scan tool, to move related connectors and wiring and observe the component operation. With the engine
running, move related connectors and wiring while monitoring engine operation. If harness or connector movement affects the data displayed,
component/system operation, or engine operation, inspect and repair the harness/connections as necessary.
You may need to load the vehicle in order to duplicate the concern. This may require the use of weights, floor jacks, jackstands, frame machines, etc. In
these cases you are attempting to duplicate the concern by manipulating the suspension or frame. This method is useful in finding harnesses that are too
short and their connectors pull apart enough to cause a poor connection. A DMM set to the Min/Max mode and connected to the suspect circuit while
testing can yield desirable results. Refer to Testing for Electrical Intermittents (See: Testing and Inspection/Component Tests and General
Diagnostics/General Electrical Diagnostic Procedures/Circuit Testing/Testing for Electrical Intermittents).
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the fault condition to appear. In such cases it may be
necessary to expose the suspect circuit to other conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the circuit to these kinds of conditions.
High Temperature Conditions
If the complaint tends to be heat related, you can simulate the condition using the J-25070 - heat gun.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses under high temperature conditions while monitoring the
scan tool or DMM to locate the fault condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal operating temperature. If a heat gun is unavailable, consider
this option to enhance your diagnosis. This option does not allow for the same control, however.
Low Temperature Conditions
Depending on the nature of the fault condition, placing a fan in front of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that provides hot or cold air). This type of tool is capable of
producing air stream temperatures down to -18°C (0°F) from one end and +71°C (160°F) from the other. This is ideally suited for localized cooling
needs. In addition, circuit cooling spray can be used to cool down a component or circuit.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or components in an effort to duplicate the concern.
Duplicating Failure Conditions
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If none of the previous tests are successful, attempt to duplicate and/or capture the failure conditions.
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Freeze Frame/Failure Records data, where applicable, contains the conditions that were present when the DTC set.
