Avalanche 4WD V8-5.3L (2011)
GMLAN Wiring Repairs
GMLAN Wiring Repairs
Special Tools
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EL-38125-10 - Splice Sleeve Crimping Tool
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J 38125-5A - Ultra Torch Special Tool
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DuraSeal splice sleeves
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A wire stripping tool
For equivalent regional tools, refer to Special Tools See: Power and Ground Distribution/Tools and Equipment.
The DuraSeal splice sleeves have the following 2 critical features:
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A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a sealing adhesive inside.
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A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low energy circuits.
The GM Local Area Network (GMLAN) System requires special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working on GMLAN connectors and terminals.
GMLAN Repairs
Note: When making a repair to any GMLAN network, the original wire length after the repair must be the same length as before the repair. If the
network is a twisted pair, the twist must be maintained after the repair is completed.
GMLAN has 2 types of networks, low speed and high speed. Low speed GMLAN has a single wire and works at slow speeds. High speed GMLAN has 2
wires in a twisted pair and works at higher speeds. For more information on GMLAN, refer to Data Link Communications Description and Operation
See: Powertrain Management/Computers and Control Systems/Information Bus/Description and Operation.
GMLAN Connector Terminal Repair
Note: A terminated lead can be used to replace damaged connector terminals for both high speed and low speed GMLAN systems. When making a
connector terminal repair on a GMLAN high speed system with twisted pair wires, do not untwist the wires more than necessary to make the repair.
If the individual terminals are damaged on any GMLAN connection, use the appropriate connector repair procedure in order to repair the terminal. Refer
to Connector Repairs See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs for the appropriate
connector repair procedure.
GMLAN Wire Repair
Note: Refer to Wiring Repairs in the service information connector end views or the vehicle schematics in order to determine the correct wire size for
the circuit you are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing in a new section of wire of the same gauge size (0.5 mm, 0.8 mm, 1.0 mm etc.). Use
the DuraSeal splice sleeves and EL-38125-10 - tool. For wiring repair, refer to Splicing Copper Wire Using Splice Sleeves See: Testing and
Inspection/Component Tests and General Diagnostics/Wiring Repairs/Splicing Copper Wire Using Splice Sleeves.
Heated Oxygen Sensor Wiring Repairs
Heated Oxygen Sensor Wiring Repairs
Caution: Do not solder repairs under any circumstances as this could result in the air reference being obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen sensor assembly must be replaced. Do not attempt to
repair the wiring, connector, or terminals. In order for the sensor to function properly it must have a clean air reference. This clean air reference is
obtained by way of the oxygen sensor signal and heater wires. Any attempt to repair the wires, connectors or terminals could result in the obstruction of
the air reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
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Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors. These materials may get into the sensor, causing poor
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that the wires inside are exposed. This could provide a
path for foreign materials to enter the sensor and cause performance problems.
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Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks, etc., could block the reference air path through the
