Thanks Jerald for the information, as you said that , the cartridges move back and forth, after you power off and on the printer, that means the carriage mechanism is working, now as the cartridges are stopping at the right side, instead of left that means the problem is with the sensor, which detect the position of the cartridges, only one thing which you can try to solve the problem and if the problem does not get solve after trying this then, you have to repair the printer.
Power off the printer and power on it again, then as soon as the cartridge move to the left side, power off the printer, so that the cartridges stop at the left side, then follow the steps below to clean the encoder strip following the steps below , which looks like the image below.
1. With the printer on, open the top cover to allow the print cartridge cradle to move to the center of the printer.
2. Unplug the power cord from the printer.
3. Slide the cradle to the far-left position.
4. Identify the semi-clear mylar encoder strip, located just behind the round, metal, cradle rod.
CAUTION: When pulling the cloth along the encoder strip in Step 5, grasp the strip gently, to ensure that the strip does not break. Pull the cloth in a right-to-left direction.
5. Moisten a clean cloth or tissue with water, then gently grasp the strip between the thumb and forefinger, and carefully pull the moistened cloth along the entire length of the strip in a right-to-left direction. Repeat this step with a different portion of the cloth to ensure that all foreign matter is removed.
6. Move the cradle to the far-left position and repeat Step 5 on the right side of the encoder strip, beginning as far right as possible. Again, gently pull the cloth in a right-to-left direction.
7. Allow the encoder strip to dry, or gently dry the encoder strip with a clean, dry cloth or tissue.
8. Position the cradle near the center, and then plug the power cord into the printer.
9. Close the top cover to allow the print cartridge cradle to move back to the right of the printer.
10. Print a self-test to ensure, that the printer is functioning properly.