Rear window defroster

Salutations from Serbia.

In January this year I bought used Nissan Micra k12 (2004) with 1.2 engine.
Since it was used, some things were messy and broken, but I managed to fix almost all of them. Almost as in, I can't yet figure out why my rear window defroster is not working and it is driving me nuts. I have double checked the electrical contacts on the window and they are good. Problem is, button is not reactive, as in not even LED signal light turns on when pressed. Under the steering wheel, I searched for broken fuses or relays but could not find any for rear defroster. Maybe I am missing some fuse/relay locations since I have only checked this one under the wheel?

If anyone have some suggestion, I would greatly appreciate it. Also, sorry if I am using some terms wrong, this is my first car and I am still getting used to fixing my own mess (or in this case someone else's :D)

Kind regards.
 
You could check the button.
In my case sticky button this is the front fascia.
The button is part of this but actual switch behind this button.
Try to remove the front part you will need to remove the unit as whole.
If this is the case the button would be sticking or stuck in the closed position.
If the button works correctly ignore my advice.
After reading John_D's guide my air con and rear screen heater light up.
if you need more info check here

I also had a broken connection at the window and this is a hard area to solder I still need to get the top part to solder and this can be difficult because of the glass and awkward area.

Sent from my ASUS_T00P using Micra Sports Club mobile app
 
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Salutations from Serbia.

In January this year I bought used Nissan Micra k12 (2004) with 1.2 engine.
Since it was used, some things were messy and broken, but I managed to fix almost all of them. Almost as in, I can't yet figure out why my rear window defroster is not working and it is driving me nuts. I have double checked the electrical contacts on the window and they are good. Problem is, button is not reactive, as in not even LED signal light turns on when pressed. Under the steering wheel, I searched for broken fuses or relays but could not find any for rear defroster. Maybe I am missing some fuse/relay locations since I have only checked this one under the wheel?

If anyone have some suggestion, I would greatly appreciate it. Also, sorry if I am using some terms wrong, this is my first car and I am still getting used to fixing my own mess (or in this case someone else's :D)

Kind regards.

Use a circuit tester to test for current at the rear window defroster, if you have 12 volts at the terminals glued to the rear glass you thereby eliminate the fault being anything but the defroster element itself, it may have hairline cracks which break the circuit and stop it working.

This may also be helpful, F45 & F46.
 
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OP
OP
bubanj93
Thank you both for suggestions and feedback. I will find some time over the weekend to look into the new info you guys provided. Cheers! :)
 
Mine failed, use gold paint to restore connections on the glass, L@@K very carefully at the elements to see if any are scored even slightly as this will cause an open circuit!:unsure:
 

John_D

Club Member
Radio Code Guru
The fuses for the heated rear screen is unfortunately in the 'Intelligent Power Distribution Module' (now there's an oxymoron if ever I saw one! :mad: )
K12 power distribution module.jpg
), under the L/H side head light. (15Amp fuses No45 & 46, marked 'RRDEF' in the picture above). You have to remove the headlight first . DO NOT try to take the top off of what appears to be the fuse box as it is not the top, it is the bottom, the fuses and relays are underneath (uncovered). You have to unclip the unit and invert it to get at them. You do not have to unplug any wiring as there is sufficient length of wire to allow you to flip the unit over...
 
OP
OP
bubanj93
The fuses for the heated rear screen is unfortunately in the 'Intelligent Power Distribution Module' (now there's an oxymoron if ever I saw one! :mad: )View attachment 72963), under the L/H side head light. (15Amp fuses No45 & 46, marked 'RRDEF' in the picture above). You have to remove the headlight first . DO NOT try to take the top off of what appears to be the fuse box as it is not the top, it is the bottom, the fuses and relays are underneath (uncovered). You have to unclip the unit and invert it to get at them. You do not have to unplug any wiring as there is sufficient length of wire to allow you to flip the unit over...

Thank you for this. I agree, the design is more than impractical.
 
OP
OP
bubanj93
Okay, so finally an update. I did everything you guys suggested and had some success. I swapped both 15 amps fuses, and voila. As they were both broken, I started the car and with the press of the button, LED light went on for the first time as I own the car. Yay right? Well sort of.


Mere seconds after I switched rear defroster on, I left the car to check if everything was okay. I arrived to a small smoking screen emanating from two recently swapped fuses. Normally, I turned off the car immediately. I double checked, I placed 15 amps fuses in right places. I've decided to look at those two fuses, and their plastic almost melted...

Although dangerous, I tried swapping both fuses with 20 amps instead of 15. Same thing happens, as the smoke starts coming from the fuse box (probably from respective wires), but this time plastic on the fuses did not melt.

Any suggestions what may be causing this, and what should I do further?
 

John_D

Club Member
Radio Code Guru
Okay, so finally an update. I did everything you guys suggested and had some success. I swapped both 15 amps fuses, and voila. As they were both broken, I started the car and with the press of the button, LED light went on for the first time as I own the car. Yay right? Well sort of.


Mere seconds after I switched rear defroster on, I left the car to check if everything was okay. I arrived to a small smoking screen emanating from two recently swapped fuses. Normally, I turned off the car immediately. I double checked, I placed 15 amps fuses in right places. I've decided to look at those two fuses, and their plastic almost melted...

Although dangerous, I tried swapping both fuses with 20 amps instead of 15. Same thing happens, as the smoke starts coming from the fuse box (probably from respective wires), but this time plastic on the fuses did not melt.

Any suggestions what may be causing this, and what should I do further?
I recon the wire feeding the rear screen heater is damaged where it passes through the 'elephants trunk' between the body and the tail gate and is shorting out there .......
 
When I'm viewing wire for this area I'm looking at the fuse being 15 amp.
Would it be okay to add a short amount to this at a higher 16.5amp for the wire gauge I think 1mm.

Sounds near enough.
I want to just add a small length to stop it tugging while I solder the tab back on.
I would like to be sure it's not too thick or high amps.
Should be Easy to get this soldered back on. I seem to not have good enough skills to get it to solder on the angle of the window.
 
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It’s getting colder, of that there’s no doubt. And while some of us are still working for home, for many others, cold mornings bring the prospect of iced-up car windscreens holding the commute or school run. Beat Maker Apps
So here are some simple steps to quickly and safely defrost the outside of your car and defog the inside, plus some tips on how to prevent the problems in the first place.
 
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