Terrain FWD L4-2.4L (2010)
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Freeze Frame, Failure Records, Snapshot, or Vehicle Data Recorder data may help with this type of intermittent condition, where applicable.
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If the intermittent is related to heat, review the data for a relationship with the following:
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High ambient temperatures
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Underhood/engine generated heat
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Circuit generated heat due to a poor connection, or high electrical load
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Higher than normal load conditions, towing, etc.
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If the intermittent is related to cold, review the data for the following:
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Low ambient temperatures-In extremely low temperatures, ice may form in a connection or component. Inspect for water intrusion.
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The condition only occurs on a cold start.
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The condition goes away when the vehicle warms up.
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Information from the customer may help to determine if the trouble follows a pattern that is temperature related.
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If temperature is suspected of causing an intermittent fault condition, attempt to duplicate the condition. Refer to Inducing Intermittent Fault
Conditions (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions) in order to duplicate the conditions required.
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 misrouted 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 lead to interference while in use, but do not fail when the accessories are not in use. 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.
Testing for Short to Ground
Testing for Short to Ground
Special Tools
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EL 39200 - Digital Multimeter (DMM)
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EL 35616-200 - Test Light-Probe Kit
For equivalent regional tools, refer to Special Tools (See: Tools and Equipment).
Caution: Refer to Test Probe Caution (See: Service Precautions/Vehicle Damage Warnings/Test Probe Caution).
The following procedures test for a short to ground in a circuit.
With a Digital Multimeter (DMM)
