Rainier AWD L6-4.2L (2007)
Throttle Position Sensor: Diagnostic Aids
Testing for Intermittent Conditions and Poor Connections
TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS
TOOLS REQUIRED
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J 35616 GM-Approved Terminal Test Kit
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J-38125 Terminal Repair Kit
When the condition is not currently present, but is indicated in DTC history, the cause may be intermittent. An intermittent may also be the cause when
there is a customer complaint, but the symptom cannot be duplicated. Refer to the Symptom Table of the system that is suspect of causing the
condition before trying to locate an intermittent condition.
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the following items:
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Wiring broken inside the insulation
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Poor connection between the male and female terminal at a connector
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Poor terminal to wire connection-Some conditions which fall under this description are poor crimps, poor solder joints, crimping over the wire
insulation rather than the wire itself, and corrosion in the wire to terminal contact area, etc.
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Pierced or damaged insulation can allow moisture to enter the wiring causing corrosion. The conductor can corrode inside the insulation, with little
visible evidence. Look for swollen and stiff sections of wire in the suspect circuits.
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Wiring which has been pinched, cut, or its insulation rubbed through may cause an intermittent open or short as the bare area touches other wiring
or parts of the vehicle.
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Wiring that comes in contact with hot or exhaust components
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Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required, in order to verify the customer concern.
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Refer to Testing for Electrical Intermittents for test procedures to detect intermittent open, high resistance, short to ground, and short to voltage
conditions.
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Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis and Vehicle Data Recorder operation.
TESTING FOR PROPER TERMINAL CONTACT
It is important to test terminal contact at the component and any inline connectors before replacing a suspect component. Mating terminals must be
inspected to ensure good terminal contact. A poor connection between the male and female terminal at a connector may be the result of contamination
or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or damaged connector seal, damage to the connector
itself, or exposing the terminals to moisture and dirt can also cause contamination. Contamination, usually in the underhood or underbody connectors,
leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper adapter. Always use the J 35616 when probing
connectors. Other causes of terminal deformation are improperly joining the connector halves, or repeatedly separating and joining the connector
halves. Deformation, usually to the female terminal contact tang, can result in poor terminal contact causing an open or intermittently open circuit.
TESTING FOR PROPER TERMINAL CONTACT IN BUSSED ELECTRICAL CENTERS (BEC)
It is very important to use the correct test adapter when testing for proper terminal contact of fuses and relays in a bussed electrical center (BEC). Use
J-35616-35 to test for proper terminal contact. Failure to use J-35616-35 can result in improper diagnosis of the BEC.
Follow the procedure below in order to test terminal contact:
1. Separate the connector halves.
2. Visually inspect the connector halves for contamination. Contamination may result in a white or green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An underhood or underbody connector that shows
signs of contamination should be replaced in its entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J-38125 , test that the retention force is significantly different between a good terminal and a suspect
terminal. Replace the female terminal in question.
FLAT WIRE (DOCK AND LOCK) CONNECTORS
There are no serviceable parts for flat wire (dock and lock) connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact:
1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are uniform and free of damage or deformation.
4. Insert the appropriate adapter from the on the flat wire harness connector in order to test the circuit in question.
CONTROL MODULE/COMPONENT VOLTAGE AND GROUNDS
