9-7X V8-6.0L (2008)
Temperature Sensitivity
*
An intermittent condition may occur when a component/connection reaches normal operating temperature. The condition may occur only when the
component/connection is cold, or only when the component/connection is hot.
*
Freeze Frame, Failure Records, Snapshot, or Vehicle Data Recorder data may help with this type of intermittent condition, where applicable.
*
If the intermittent is related to heat, review the data for a relationship with the following:
^
High ambient temperatures
^
Underhood/engine generated heat
^
Circuit generated heat due to a poor connection, or high electrical load
^
Higher than normal load conditions, towing, etc.
*
If the intermittent is related to cold, review the data for the following:
^
Low ambient temperatures-In extremely low temperatures, ice may form in a connection or component. Inspect for water intrusion.
^
The condition only occurs on a cold start.
^
The condition goes away when the vehicle warms up.
*
Information from the customer may help to determine if the trouble follows a pattern that is temperature related.
*
If temperature is suspected of causing an intermittent fault condition, attempt to duplicate the condition. Refer toInducing Intermittent Fault
Conditions (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Inducing Intermittent Fault Conditions) in
order to duplicate the conditions required.
Electromagnetic Interference (EMI) and Electrical Noise
Some electrical components/circuits are sensitive to electromagnetic interference (EMI) or other types of electrical noise. Inspect for the following
conditions:
*
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.
*
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.
*
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
toChecking Aftermarket Accessories (See: Testing and Inspection/Component Tests and General Diagnostics/Checking Aftermarket Accessories).
*
Test for an open diode across the A/C compressor clutch and for other open diodes. Some relays may contain a clamping diode.
*
The generator may be allowing AC noise into the electrical system.
Incorrect Control Module
*
There are only a few situations where reprogramming a control module is appropriate:
^
A new service control module is installed.
^
A control module from another vehicle is installed.
^
Revised software/calibration files have been released for this vehicle.
Important:: 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.
*
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 toControl Module References (See: Testing and Inspection/Programming and Relearning/Control Module
References) for replacement, setup, and programming.
Testing for Short to Ground
Testing for Short to Ground
Notice: Refer toTest Probe Notice.
The following procedures test for a short to ground in a circuit.
With a DMM
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit.
