Hi, I have been told the same that, the rear window washer tank comes from the front tank but I have filled my front tank and when I wanted to clean the rear window the wiper moves but water didn't come. Does anyone know how to fix this ?
Oops...just saw that you have a 2007 Sorento...Should go to the 2007 Sorento forum. I'll leave this for the benefit of 2011-2013 Sorento owners.
There's the washer fluid reservoir, washer pump, tubing and washer nozzle. It's one of those items.
The pump is attached to the bottom of the reservoir. If fluid comes out for the front/windshield, it's probably not the pump failing. However, the pump is used for both the front and back so there could be something internal causing the issue there.
If the front still works, you can try swapping the front and back hoses on the pump to see if the back starts to work and front stops. That would mean you need to replace the pump. If the back still doesn't work, then there's something wrong with the hose going to the back or the rear washer nozzle.
If both front and back don't work, check the pump filter. The pump has a filter to prevent stuff going into the pump. If fluid doesn't come through for front and back, check if the filter is clogged. You can remove the debris by hand.
Good video here:
It shows you how to get to the reservoir, clear the pump filter and where the hoses are for the pump. Replacement pumps are inexpensive also. Around $15 to $25 US.
It could be a break in the tubing going to the back or perhaps the tubing is clogged somewhere. If it's a break, you'll have to follow the tubing to find where the break is. Not sure where the hose is routed. It would either be along the bottom or through the interior maybe going up through the A pillar through the headliner...not sure. You can follow the hose from the back and from the front to see where it goes. Replacement hose is inexpensive.
Look around Youtube. Most of the videos for washer fluid issues are applicable also to our Sorentos.