I’m not to bad at tinkering, does anyone have an idea how I would take a look at fixing this myself instead of taking this to a garage, and if possible picture/guide of having to remove interior trim, just got the car as a replacement to written off one, so don’t wanna break anything yet, I could take it back to where I bought it, but don’t want to alienate them if it’s something small. 

First step would be checking if the pump is making a noise when you try to operate it, similar to when you operate the front washers.

Then maybe getting the wheelarch liner off to access the pump/washer bottle where you could see if it’s pumping fluid but hose blocked, pump not working, or not getting voltage to it when you operate rear washer. Pretty sure there isn’t a physical relay for the washer, just handled internally in the GEM/passenger fusebox but you’d be able to check voltages at various points to narrow down any power issues. 
 

Washer pumps are known to fail, have replaced mine in the past but can’t remember if just one function stopped working or both. Motor works on a single supply being reversed to operate front or rear washer circuit

17 minutes ago, Leigham said:

I’m not to bad at tinkering, ...

When you press the washer switch, can you hear the motor attempt to work, or is it totally dead?

EDIT

Dam @troy45, you type fast LOL

I can indeed hear the pump working 

2 minutes ago, Leigham said:

I can indeed hear the pump working 

In that case, the pump appears to be working. Can you see a water leak from the rear roof headline in the unlikely event the washer tube has come adrift?

I don’t see any at the moment when I get time, I’ll run a tap over the rear and hold the pump for a while, right now it makes a right racket with the rear wiper going as it’s dry as a bone.

Ok, held it down for a while roof seems to be dry and no water elsewhere from what I can see.

Where does the pipe run through the car as I might slice, put a connector so I can see if it’s a problem at the front or the back and potentially run a new tube. 

29 minutes ago, Leigham said:

..., right now it makes a right racket with the rear wiper going as it’s dry as a bone.

Lift the wiper off the screen LOL

5 minutes ago, StephenFord said:

Lift the wiper off the screen LOL

Yeah I thought of that just as I said it, no visible wet spots anywhere 

Mine does exactly the same. I can hear the pump but no water at the back, or showing anywhere in the car. I think the pump is blocked so will have to remove it to clean it out. Not just yet though, it's too damn hot at the moment.

Hidden in the head lining at the back of the car near the tailgate is a small inline non-return valve. They are well known to fail and become stuck closed.

You can either replace the inline valve, or as many have done, just remove the valve and join the pipes together. Straight inline pipe connectors are available from the likes of Halfords or eBay.

Examples:

https://www.halfords.com/motoring/tools/fuses-electricals-and-fixings/fixings/halfords-in-line-connector-fixg225-727182.html

https://www.halfords.com/motoring/tools/fuses-electricals-and-fixings/fixings/halfords--hose-connector-straight-fixg226-727190.html

https://www.ducocarparts.co.uk/products/genuine-ford-1554051-ka-rear-windscreen-washer-pipe-hose-connector

Same with the missus car last year. After Googling, a common place for the pipe to pop off is...

Open the boot, removed panel to the right. Have someone in the car operate the rear washer. Sure enough, there it was. Popped pipe back on. Made it more secure with a small zip-tie. Job's a good'n. 

On 7/11/2025 at 11:27 PM, unofix said:

Hidden in the head lining at the back of the car near the tailgate is a small inline non-return valve. They are well known to fail and become stuck closed.

You can either replace the inline valve, or as many have done, just remove the valve and join the pipes together. Straight inline pipe connectors are available from the likes of Halfords or eBay.

Examples:

https://www.halfords.com/motoring/tools/fuses-electricals-and-fixings/fixings/halfords-in-line-connector-fixg225-727182.html

https://www.halfords.com/motoring/tools/fuses-electricals-and-fixings/fixings/halfords--hose-connector-straight-fixg226-727190.html

https://www.ducocarparts.co.uk/products/genuine-ford-1554051-ka-rear-windscreen-washer-pipe-hose-connector

Do you have a picture of where abouts to look? 

On 7/12/2025 at 12:13 AM, Tonikeys said:

Same with the missus car last year. After Googling, a common place for the pipe to pop off is...

Open the boot, removed panel to the right. Have someone in the car operate the rear washer. Sure enough, there it was. Popped pipe back on. Made it more secure with a small zip-tie. Job's a good'n. 

Can you take a picture of which panel