Manufacturer communication — 2006 GMC YUKON DENALI XL

• Applies to 2018 and prior GM passenger cars and trucks.

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  2018 and Prior GM Passenger Cars and Trucks

• Customers may report various issues related to high or low speed data bus traffic.

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  Customers may comment on various issues with their vehicle related to high or low speed data bus traffic.

• Bus or LAN traffic may stay active, leading to a discharged vehicle battery.

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  Bus or LAN traffic may stay active leading to a discharged vehicle battery.

• The radio may not shut off after the vehicle is shut down.

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  The radio may not shut off after shutting down vehicle.

• C0561 may be stored in the EBCM, leading to a traction control issue.

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  C0561 stored in the EBCM leading to a traction control issue.

• The SES/MIL light may be set with numerous communication DTCs such as U0100, U0101, U186B and U1862.

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  SES, MIL or CEL light set and numerous DTC communication codes such as U0100, U0101, U186B and U1862.

• The transmission may not shift for one key cycle (TCM in default mode).

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  Transmission may not shift for one key cycle (TCM in default mode).

Possible causes

• Monitoring devices and other electronic accessories such as aftermarket cruise control or police speed checking devices (RADAR or LIDAR) may cause one or more of the listed concerns.

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  Monitoring devices, along with othe electronic accessories such as aftermarket cruise control, or police speed checking devices (RADAR or LIDAR) may cause one or more of the concerns listed above.

Steps to confirm (in the document’s order)

• If normal SI diagnostics identify nothing else, check for a tracking or maintenance-scheduling device plugged into the ALDL / Data Link Connector (DLC).

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  If nothing else can be identified as the root cause of the issue after normal diagnostics as found in SI, check for a device plugged into the Assembly Line Diagnostic Link (ALDL) or Data Link Connector (DLC) for tracking and/or maintenance interval scheduling.

Repair

• If the concern is resolved by removing the DLC interface device, tell the customer the result and that they should work with the device supplier for further resolution.

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  If the customer’s concern is resolved by removing the DLC interface device, inform the customer of the results, and that they should work with the supplier of the device for further resolution.

Caution

• The bulletin focuses on full size trucks, full size vans and other fleet vehicles, but could apply to any vehicle.

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  This bulletin is being written with a focus on full size truck and full size van along with other fleet vehicles, but could apply to any vehicle.

• Some devices have a second DLC connector; the harness and device can be hidden, and the technician may not notice the diagnostic connector is not in the factory location.

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  This device has another DLC connector on it. The rest of the harness along with the device can be placed out of sight hidden from the technician, who may not notice the diagnostic connector is not in the factory location.