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GMLAN Wiring Repairs




GMLAN Wiring Repairs

Special Tools
* EL-38125-10 - Splice Sleeve Crimping Tool
* J 38125-5 - Ultra Torch Special Tool
* DuraSeal splice sleeves
* A wire stripping tool

For equivalent regional tools, refer to Special Tools (Tools and Equipment).

The DuraSeal splice sleeves have the following 2 critical features:

* A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a sealing adhesive inside.
* 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 (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 (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 (Splicing Copper Wire Using Splice Sleeves).