Procedure notes
The video above shows you how to change a burnt out front turn signal bulb on your 2021 GMC Sierra 3500 HD. If the turn signal (also known as a blinker or flasher) blinks rapidly or doesn't blink at all / stays stuck when engaged, this is your Sierra 3500 HD's way of telling you that a turn signal bulb is burnt out. Troubleshooting for burnt out turn signal bulbs in your Sierra 3500 HD is relatively easy - turn your hazard lights on and check the front of your Sierra 3500 HD and then the back, whichever side is not illuminating is the side with the burnt out bulb. We recommend that you change both the driver and passenger side bulbs at the same time as they get dimmer over time and if one is out, then the other one is likely to burn out soon.
When changing the turn signal bulb in your Sierra 3500 HD, be careful not to touch the glass portion of the bulb with your fingers as this will cause the bulb to burn out prematurely.
查看中文对照 · Chinese translation
上述视频展示了如何更换您 2021 GMC Sierra 3500 HD 车辆前转向灯烧坏的灯泡。 如果转向灯（也称为闪烁灯或闪光灯）快速闪烁或完全不闪烁、在开启时一直保持亮着，这是Sierra 3500 HD在告诉你转向灯灯泡已烧坏。 排查 Sierra 3500 HD 上烧坏的转向灯灯泡较为简单：打开危险报警闪光灯，先检查 Sierra 3500 HD 车头，再检查车尾；哪一侧不亮，哪一侧的灯泡就可能已烧坏。 我们建议您同时更换驾驶员侧和乘客侧的灯泡，因为随着时间推移，灯泡会变暗，如果其中一个灯泡损坏，另一个灯泡也可能会很快烧坏。
更换 Sierra 3500 HD 的转向灯灯泡时，请勿用手指触碰灯泡的玻璃部分，否则可能使灯泡提前损坏。