Disco 2 TD5 HRW blowing fuses

meego said:

I also wonder why if it’s water ingress causing the issue, does drying it out not solve the issue ??

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Cos water can let corrosion behind and that's electrical conductor

sierrafery said:

Cos water can let corrosion behind and that's electrical conductor

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So would I be correct in saying if you find that corrosion, get rid of it and make good, you should solve your problem.?? I always ensure the earth points on my 90 are good, but that’s a much simpler system. I still struggle with it though

Andy Warren said:

If you look at the pic I've removed 'pin' 4 with the brown/ purple wire from C0582 which is the brown connector in the background. If I now plug all the connectors back into the fuse box with 'pin' 4 hanging loose man & switch the HRW on & it still blows fuse 8 then I'll know it's the fuse box at fault somewhere, however if it doesn't blow it, it will be a direct short on that brown/purple wire somewhere as I've already isolated the mirrors & HRW element. I've put the MM on continuity (beep) & checked between that brown/purple wire & earth & the meter beeps so it looks like a short on it somewhere but I'll continue with checking the fuse box whilst I'm here, hope that's as clear as mud View attachment 252112

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Spot on!

So I can now confirm that with 'pin' 4 removed from C0582 it doesn't blow fuse 8, yippee £260 odd beer tokens saved. I've checked the drivers door loom C0480 & the brown/purple in that doesn't go to earth so that's eliminated. I've just to do the same to the passenger side door loom & then the wiring to the rear of the vehicle to the HRW !
I can also confirm the electrical library is WRONG in saying C0583 is above C0582 on the fuse box see pic of embossed connector no's. Just a quick question if I leave pin 4 out of C0582 until I find the short will that affect any other circuits ? As when I use the demist for the windscreen it automatically puts the front & rear heated screens on.
I can't thank everyone enough for their contributions in making what seemed a dauting issue straight forward to diagnose (the repair might be a bit more involved)

So I can now confirm that with 'pin' 4 removed from C0582 it doesn't blow fuse 8, yippee £260 odd beer tokens saved.

meego said:

I wish I knew what was going on here. No matter what I do, I seem to be electric dyslexic.
When you guys say, remove pin, do you mean physically remove the pin. I also wonder why if it’s water ingress causing the issue, does drying it out not solve the issue ?? Or does water cause issues in ECU’s etc even if they don’t actually get wet
I’m not that thick that I don’t know water can kill a modern car by the way

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HI meego, in my case it wasn't water ingress, to the fuse box at least, that's caused this issue but your right if water is dried out straight away in most cases you'll get away with any long lasting problems. As the fuse box contains a relay soldered to it's board for the HRW/mirrors, water could have shorted/burnt this out & as you can't buy the relay separate means lots of beer tokens for a replacement. The word pin is just used for any wire terminal within a connector & as you can see from my previous picture in this case it's a female spade connector & not a pin at all (although there are round & more like a pin wire terminals as your probably aware).
Hope your keeping well, all the best.

Andy Warren said:

So I can now confirm that with 'pin' 4 removed from C0582 it doesn't blow fuse 8, yippee £260 odd beer tokens saved. I've checked the drivers door loom C0480 & the brown/purple in that doesn't go to earth so that's eliminated. I've just to do the same to the passenger side door loom & then the wiring to the rear of the vehicle to the HRW !
I can also confirm the electrical library is WRONG in saying C0583 is above C0582 on the fuse box see pic of embossed connector no's. Just a quick question if I leave pin 4 out of C0582 until I find the short will that affect any other circuits ? As when I use the demist for the windscreen it automatically puts the front & rear heated screens on.
I can't thank everyone enough for their contributions in making what seemed a dauting issue straight forward to diagnose (the repair might be a bit more involved)View attachment 252116

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I'm really pleased you have saved all that beer and we are pleased to help. Pin 4 of CO582 only supplies the HRW and door mirror heaters, so you can safely leave it out (I'd wrap it in tape just so it doesn't come into contact with anything it shouldn't) until you find the cause of the problem.

Think the inside of the HRW switch needs attention

Andy Warren said:

Think the inside of the HRW switch needs attention View attachment 252123

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A good clean up wouldn't go amiss!!

Andy Warren said:

So I can now confirm that with 'pin' 4 removed from C0582 it doesn't blow fuse 8, yippee £260 odd beer tokens saved.

HI meego, in my case it wasn't water ingress, to the fuse box at least, that's caused this issue but your right if water is dried out straight away in most cases you'll get away with any long lasting problems. As the fuse box contains a relay soldered to it's board for the HRW/mirrors, water could have shorted/burnt this out & as you can't buy the relay separate means lots of beer tokens for a replacement. The word pin is just used for any wire terminal within a connector & as you can see from my previous picture in this case it's a female spade connector & not a pin at all (although there are round & more like a pin wire terminals as your probably aware).
Hope your keeping well, all the best.

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I’m good mate, as are you I hope. But if your crawling around in footwells I’m assuming your fine
Your photo of the cable end out of the block shed some light on my query. I had no idea those blocks were just male female spade connectors. Every days a school day eh ?

Found the short & it was all of my own doing, when I replaced the tailgate door hinges last year, I'd trapped the single wire to the HRW element. I'll chop that section out & make good with some insulated bullet connectors.

Sorted

Andy Warren said:

Sorted View attachment 252140

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Looks good!

Finding and resolving a problem feels so good....