I bought three Yoga C740-15IML for my school and we've been using them for two years now. I found that two of them had already started having issues with the USB-C port. It doesn't work at all. 

I tried all updates on Lenovo and Windows and still doesn't work. It is Windows 11 Pro, and we were using the port with the ethernet adaptor.

It was fine when it was still Windows 10.

There is no message or notification when I plug in.

I scanned the laptop using Lenovo software to check if there were any updates.

I will try safe mode and system restore.

Just wanna add more about the symptom.

There are two USB-C ports on the laptop and the one next to the power symbol still works. The other port doesn't work. This symptom is identical on both laptops. 

I just tried the power drain method on both laptops, and they both work!

What was the reason? I used both ports to charge the laptop, did that cause the issue?

@itmanagerbia wrote:

I just tried the power drain method on both laptops, and they both work!

What was the reason? I used both ports to charge the laptop, did that cause the issue?

Thanks for the update,

It's nice to know that power drain did the trick, great job!

Charging the devices using the USB-C port should not cause any performance-related issues on the machines. Though, it appears that the machines only need to be hard reset for the ports to work again.

I hope I was able to provide all the help and assistance you needed. Please feel free to post again anytime at Lenovo Community since you're always welcome here!

Regards,
Adriel_Lenovo

I'm having the same issue on my Yoga C740-14IML (Windows 10). In my case, both USB-C ports stopped working about two weeks ago, (first, the one that is closer to the audio jack port, then the second, 4-6 weeks later). They are unable to take charge or recognize/support any USB devices.  Concerned that I may lose my personal files, I operated the laptop on battery power while I was transferring the critical information to a flash drive using USB-A port. That process resulted in battery power draining to 36%. Now I'm afraid to turn it on again because I want to have at least some juice left for an expert to be able to install a driver, do a diagnostic, or anything else on it.

What would you recommend I do in my situation? Should I also try the hard reset by powering up the laptop, waiting until it fully boots, followed by pressing and holding the power button for a few seconds to shut it down?

I'm very happy for the original poster who was able to find a solution for his problem. I'm afraid that in my case, the problem could be more serious. The reason I think it could be more serious is that I don't see the charging indicator light between the USB-C ports working at all. When I had to deal with a similar problem a couple of years ago, it was working (glowing orange) while the power cord was pugged in, and draining the battery power to zero solved the problem.

But today, it's not working, suggesting that this problem may not be solved as easily.

What do you think?

Hi tnoulm,

Welcome to the Lenovo Community!

I'm sorry to read about the issues you're experiencing with your Yoga C740-14IML. It's understandable that you're concerned about the situation.

Firstly, I would recommend you to back up all your important data to an external storage device or cloud storage to prevent any data loss.

You can try the hard reset method as it has worked for some users. To do this, power up the laptop, wait until it fully boots, then press and hold the power button for a few seconds to shut it down.

However, given that you mentioned the charging indicator light is not working, it might be a hardware issue. If the hard reset doesn't work, I would recommend you to contact Lenovo Support or visit a local authorized service center for further assistance.

You can check the warranty status of your product here and find a local authorized service center here.

Hope this helps you out.

Thanks,
Adriel_Lenovo