No extension cord comes with new Mac.

scotpondonyahoo wrote:

I tried using old one. It doesn’t work with Apple C cable BUT it does work if I use a different brand C cable. What’s up?

I have had no issue using a older 3 prong extension from an older magsafe charger block to the new USBC charger block?

What could the issue be....(?)

Power Adapter Extension Cable - Apple

scotpondonyahoo wrote:

The Macs use the new USB-C charging cord

This is a true statement. Refer to the screenshot below.

https://www.apple.com/macbook-pro-16/specs/

Perhaps you should start from the beginning. Describe the assistance you are seeking.

"Sorry, but that is not the solution. I have tried plugging the block into two different extension cords. It does not work. I don't get power unless I plug the block into the wall socket."

Then your extension cord is damaged. I use an extension cord every day and have done so for years.

And, the Walmart replacement C cord gives me power when the block is plugged into any of the 3 extension cords.

To reiterate John Galt's question, what is this thing you're calling a "C cord"? That's not a commonly used term. With a new Mac notebook, Apple provides an AC adapter (or charger, if you prefer - that's the thing that plugs into the wall) and a USB-C charge cable (connects to the charger on one end and the computer on the other). "C cord" sounds like shorthand for the USB-C charge cable. It that's what you're referring to, then it sounds like you have a bad USB-C charge cable and need a replacement. Since the AC adapter and USB-C charge cable are covered by the same warranty as your Mac, Apple should provide a replacement if it is not working (assuming it's undamaged).

If that cord is not long enough, you need an extension cord between the AC adapter and the wall outlet, not a longer USB-C charge cable.

It wasn't clear. It's still not. Most of the discussion (based on the title of your post) has been around extension cords.

scotpondonyahoo wrote:

Again, my old ext cord does work with a replacement C Cord whereas the Apple C cord only works when I plug the block Directly into a power outlet..

What you said there is that your old Power Adapter Extension Cable works with the Walmart USB-C cable, and the Apple USB-C charge cable works when the power adapter is plugged directly into the wall.

If you can plug the AC power adapter into the wall and the Apple Apple USB-C charge cable delivers power to your computer, both of those components are functioning. If you then connect the AC power adapter to a standard surge protector and get no power to the computer, the problem is the surge suppressor.

Once again, I'll quote John Galt:

Perhaps you should start from the beginning. Describe the assistance you are seeking.

Your image shows only two extension cords. An extension cord has a plug on one end and receptacle (or more than one) for that same plug type on the other end. I think your lack of clarity on the types of cords we're discussing is a big part of the problem.

• Apple Power Cables (for portable AC adapters) from OWC:

https://eshop.macsales.com/shop/accessories/cables/apple-power-cables

When in stock, may be new; or tested good and noted as such.

Site shows two 1.8M official Apple power cables, per question.

Both new. This reputable Mac vendor has other useful things.

1.8 Meter (72") Apple Genuine AC Power Cable. Bulk Packaged $6.79

1.8 Meter (72") Apple Genuine AC Power Cable (not bulk) $7.75

While perusing second-hand stores, I'm almost always on lookout

for extra accessories such as these official Apple cables, & adapters.

Most of mine were only 50 cents and appeared unused. And fit.

Again, use any extension cord. Any with the correct plug for your country will work.

Some examples: https://www.amazon.com/Extension-Cords/b?ie=UTF8&node=495312

If the charger brick works when connected directly to the wall socket and it does not work when connected to an extension cord, the problem seems obvious to me. Bad extension cord..