LaCrosse FWD L4-2.4L (2011)
Electromagnetic Interference and Electrical Noise
Some electrical components/circuits are sensitive to electromagnetic interference or other types of electrical noise. Inspect for the following conditions:
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A mis-routed harness that is too close to high voltage/high current devices such as secondary ignition components, motors, generator etc.-These
components may induce electrical noise on a circuit that could interfere with normal circuit operation.
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Electrical system interference caused by a malfunctioning relay, or a control module driven solenoid or switch-These conditions can cause a sharp
electrical surge. Normally, the condition will occur when the malfunctioning component is operating.
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Improper installation of non-factory or aftermarket add on accessories such as lights, 2-way radios, amplifiers, electric motors, remote starters,
alarm systems, cell phones, etc.-These accessories may create interference in other circuits while operating and the interference would disappear
when the accessory is not operating. Refer to Checking Aftermarket Accessories (See: Testing and Inspection/Component Tests and General
Diagnostics/General Electrical Diagnostic Procedures/Checking Aftermarket Accessories).
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Test for an open diode across the A/C compressor clutch and for other open diodes. Some relays may contain a clamping diode.
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The generator may be allowing AC noise into the electrical system.
Incorrect Control Module
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There are only a few situations where reprogramming a control module is appropriate:
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A new service control module is installed.
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A control module from another vehicle is installed.
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Revised software/calibration files have been released for this vehicle.
Note: DO NOT re-program the control module with the SAME software/calibration files that are already present in the control module. This is
not an effective repair for any type of concern.
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Verify that the control module contains the correct software/calibration. If incorrect programming is found, reprogram the control module with the
most current software/calibration. Refer to Control Module References (See: Testing and Inspection/Programming and Relearning) for
replacement, setup, and programming.
