At times i get a message 14 no toner cart and then i am unable to make prints

maybe an ic chips or an hp toner bias plate that contact the toner cartridge

Ensure that the Toner Cartridge is installed correctly (fully
seated into the printer). Try a new Toner Cartridge. If the
problem continues, try this

14 NO EP CART Message
The printer detects the presence of the Toner Cartridge and the
level of toner present in the cartridge through the condition of the
ANTIN signal. The ANTIN signal becomes part of the serial data
stream used to communicate with the DC Controller (see Figure
7-5 for cartridge components). Troubleshoot the 14 NO EP CART
(or INSTALL TONER CARTRIDGE) message as follows:
1 Reseat the Toner Cartridge. Try a new or known good Toner
Cartridge.
2 Check the High Voltage Contacts for damage. If the contacts
are dirty or damaged, clean the contacts after the repair.
3 Replace the High Voltage Power Supply.
4 Check and reseat the HVPS cable.
5 Replace the DC Controller.

Either drum defective, not sitting in correctly,or toner has dumped in unit covering drum contacts!

when top door , and check for the sensor switch

Its just a warning that there is a minimum amount of toner left!As soon as all the toner is done it will print faded!Get the new cart for incase that happens!

Check the flux capacitor, those usually go out on brother faxes.
I just replaced mine last week, same problem.

Are you using third party toner, or OEM? Toner cart has small chip on it that the machine reads and is being told not OEM toner

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/normanj_7893313f0751935f

14 NO EP CART Message
The printer detects the presence of the Toner Cartridge and the
level of toner present in the cartridge through the condition of the
ANTIN signal. The ANTIN signal becomes part of the serial data
stream used to communicate with the DC Controller (see Figure
7-5 for cartridge components). Troubleshoot the 14 NO EP CART
(or INSTALL TONER CARTRIDGE) message as follows:
1 reseat the Toner Cartridge. Try a new or known good Toner
Cartridge.
2 Check the High Voltage Contacts for damage. If the contacts
are dirty or damaged, clean the contacts after the repair.
3 Replace the High Voltage Power Supply.
4 Check and reseat the HVPS cable.
5 Replace the DC Controller

It has a chip on the toner cartridge, chip is bad. replace
Sometimes the sensor in the machine goes bad. replace

pc stands for photoconductor or print cartridge or in layman's term toner

the toner has reached its expected life or toner has ran out