I just bought a yamaha rx z1. i try to pluging to use the subwoofer is not working

you can connect Yamaha YST SW800 at the back of your receiver

( label =subwoofer )

http://uk.yamaha.com/en/products/audio-visual/speaker-systems/subwoofers/yst-sw800_black__u/?mode=model

No manual for your receiver? Find it here and read it.

http://www.retrevo.com/support/Yamaha-RX-V365-Receivers-manual/id/23270ag802/t/2/

You have to tell it there is a sub then, tests the sub then make some bass management choices.

Register and download the manuals for free at retrevo.com

http://www.retrevo.com/support/JBL-ES150P-Subwoofers-manual/id/7098bh340/t/2/

Have you tried just turning the subwoofer amp

Hello,
Check and make sure that you dont have any wires shorted out. Also make sure that its not in a tight enclosed space because it can overheat quickly. It also wouldnt hurt to hard-reboot the unit. Simply turn it on, then unplug power from it for about 15 seconds. If non of these options shed some light, than you might need to get it serviced.
Good Luck

Without being able to access the receiver in person, the best advice I can give you is to sit down with your user manual and follow the instructions. You'll find, starting on page 85, the necessary settings for hooking up a subwoofer to the receiver. If you don't have the manual, you can obtain a pdf file at Yamaha.com: http://www.yamaha.com/yamahavgn/Documents/YEC/AV_Receivers/Manual/RX-V663_U-1.pdf

Most likely the plug is ok but the level control for the subwoofer will need to be readjusted in the receiver, If the level cannot be raised making sure your source being used has subwoofer information, then there could be a problem in that circuit.

If I understand you correctly, your subwoofer does not have RCA jacks but speaker terminals only. This should solve your issue but I have seen less expensive ones in the past.

Check that the speaker setting on the receiver is set to large not small. (if you have 6inch or larger woofers)

If you have only small speakers you will need a subwoofer.

how can i hook a subwoofer into yamaha RX-V850

The problem is IC 451, (Yamaha Part # XU814A00) (Number on part PQ05RD11 Made by Sharp). It's a + 5V 1A Voltage Regulator.
It's located at the bottom of the power supply board mounted to the front heat sink. It's a four legged TO220 Package outline. So don't try to slip a three legged 5 volt regulator in it's place. This can cause serious damage and headaches. Change this part and everything should be good.