Improper Headlamp or Turn Signal Operation Due to GM Accessory Illuminated Emblem

Some 2020-2022 Sierra 1500, Sierra 2500/3500; and 2021-2022 Yukon models may have a driver-side headlamp or turn signal that stays on, flickers or is inoperative. The dealer-installed GM Accessory Illuminated Emblem also may be inoperative. These conditions may be caused by water intrusion from the GM Accessory Illuminated Emblem. (Fig. 11)

Fig. 11

Inspect for water intrusion and corrosion at the GM Accessory Illuminated Emblem connection (Fig. 12) as well as the driver-side headlamp connector and the inline GM Accessory Illuminated Emblem harness. (Fig. 13)

Fig. 12

Fig. 13

If water intrusion or corrosion is found, perform any necessary repairs to the headlamp connector on the body harness and clean the headlamp assembly terminals.

To prevent further improper operation, bypass the GM Accessory Illuminated Emblem harness by plugging the original headlamp connector from the body harness back into the headlamp assembly. This will temporarily disable the Illuminated Emblem. Permanent repair information will be released when available.

TIP: The headlamp assembly is not currently known to be a source of the water intrusion.

If there is not any water intrusion or corrosion found at any of the connectors, the GM Accessory Illuminated Emblem is not the source of the condition. Follow normal SI diagnostics. The GM Accessory Illuminated Emblem harness should still be disabled to prevent any improper operation in the future. Be sure to verify proper headlamp operation.

The ends of the GM Accessory Illuminated Emblem harness should be connected together and secured to prevent movement. (Fig. 14)

Fig. 14

Refer to #PIT5918 for additional information.

– Thanks to Jim Will

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One Comment

  1. Rick Tieken says:

    Hello, do we have any idea when a revised wiring harness will be available? We have a couple of customers with this accessory and would like to be able to provide them with an update.

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