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Discussion Starter #1
My 1998 P38 totally died last night when I switched the headlights to main beams - the engine died as did all electrics.

After research on here, I 'jiggled' (technical term) the main power connection post on the fuse box behind the battery (shown in the photo) and heard a relay click. Sure enough, I now had power and was able to start the car and move it to a place of safety..... just before the power totally died again!

As a new fuse box seems to cost over £200, has anyone managed to repair a faulty post connection like this? The visible connection at the top looks and feels sound enough, so I believe it is no longer making a good connection with the circuit board inside the fuse box......but that doesn't sound too hard to repair if there is good enough access?

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I would clean the connector(you may have to reset windows) and swap the relay that you heard click with the passenger windscreen heater(something you won't use) to see if a relay is sticking.
 

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Discussion Starter #3
After much research, I decided to try repairing the PCB/post connection before considering new or used fuse box replacements.

I probably wouldn't have been brave enough to do that without great help from my friend Ed Quayle (a factory-trained mechanic), but we had a go at it last night....and I think we successfully repaired it!

I thought I would show some here photographs of what is involved, as they might be useful to anyone else with the same problem. I certainly would have loved them before starting! (I'd have included more but I can't upload more than 1 image at a time, for some reason!)

The main issue was that the post which the thick red lead from the battery bolts onto no longer had any solder on the bottom connecting it to the PCB. As you can see in one photo, the bottom of the post has 2 semicircular feet which go through the PCB and are soldered to the copper trace in order to send the +12v around the board. Over time, I guess vibration cracks the solder and you end up with increasing resistance there until eventually the heavy current running through it (50A or more) drops enough voltage to prevent the circuits being fed getting the full 12V they need to work.

My own biggest problem (as Ed did all the removal and disassembly) was providing enough heat from my soldering iron to allow solder to run smoothly over that thick post, as it was happy to steal all the heat! Fortunately, I found a bigger bit for my 50W iron and that was just able to melt enough solder around the post to do an acceptable job. You can see in the photo that it is not as smooth as one would like, but I think it is OK.

Other than that issue with the post, the rest of the fuse box and PCB were in remarkably good shape. There was a little darkening of the PCB in one spot, but scraping and examining it showed it to be not too bad. The fold looked worrying at first, as some breaks were evident....but these turned out to be tiny slivers of the plastic substrate - not the important copper trace.

After reassembly of the fuse box and reinstallation of all the components, it was then returned to the car (with the main door open, just to be safe!) - and it seems to be fixed!

If you look carefully, you might note from the photos that Ed did not disconnect the battery - he simply removed the feed to the fuse box and tucked it carefully out of harm's way. This avoided the worrying issues about the car locking up, EKA codes, etc. The remote didn't work, which worried me until Ed locked and unlocked the door with the key....which restored the fob's operation just fine. He then needed to reset the windows and sunroof (he knew the procedure as he briefly had a P38 himself recently, as you may recall).

We tried most of the car's accessories and all seemed fine. We also felt the fuses & relays and all seemed quite cool. Just one - bottom left in the photos, feeding the blower I think - worries me a little as it does seem quite warm.


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The main power stud, and indeed the 3 main feed studs on the underside are soldered to the PCB internally.
You could get to them by completely dissembling the fusebox, however this would be best accomplished with the use of an industrial grade desoldering tool. You will have to separate the 2 boards to get to the solder pad for the stud.

It could be done with a decent iron and solder wick as well.
I have these tools, and have bought new ones for the 3 I have replaced...............Someday, I will rework the old ones........

First, remove the red wire, clean the mating surfaces, and re tighten. This may be the only issue......Look for scorching at the base of the stud, as high resistance will cause it to overheat, to the point where it will melt the solder and loosen the connection internally.
 

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Yes, not easy to get apart. One fellow cut all the connecting links between boards and then removed each piece individually. Then use solder wick to clean up all solder and use short lengths of solid copper wire for new links.
 

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the fitting looks tight I would cut of the heat shrink make shore the crimp is good as well as clean contact surfaces
 

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You can see where the plastic has been getting hot, so it has probably lost connection where the bolt connects to the pcb. Here's https://www.rangerovers.net/repairdetails/electrical/fusebox.html#dismant how to get into it to repair it but in all honesty, it's going to be far better to just replace with a new fusebox. Not worth bothering with a 2nd had one and there's 3 different ones for a V8 (the one you need is this one https://www.island-4x4.co.uk/fuse-petrol-9798-genuine-amr6476-p-3484.html) and two different ones for a diesel so it would be https://www.island-4x4.co.uk/fuse-25td-9498-genuine-amr3376-amr6406-amr6477-p-4613.html. No idea why a diesel one is more expensive as there's only a few slight differences.
 

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I thought about repairing my fusebox, be once I started to take it apart it started to come apart. Was to degraded to save, somebody has recommended to me to change them every five years.
 

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I thought about repairing my fusebox, be once I started to take it apart it started to come apart. Was to degraded to save, somebody has recommended to me to change them every five years.
"Somebody" want's to sell you a LOT of fuse blocks!
5 years?? I think Not!
If he had said 15 years?......Well, now this begins to make sense in my experience.
Best is to wait for it to start acting up and replace it then. These do not degrade by age as much as mileage and high heat.
 

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BigWing,
There is a lot of good advise here to follow. I have a 1998 Range Rover, P38, 4.6 L V8-GEMS Engine and had RL7 burn issues, with connector wobble, bad solder connections, etc. I added the 2 additional wires and other details found here:
http://rangeroverworld.blogspot.com/2010/02/fuse-box-relays.html
Since then I have driven her 2 days at 13 hours the first day and another 10 hours the second day with no electrical issues what-so-ever!
Best Wishes,
64Chris
 

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Great job on the repair, and the documentation! Thanks for posting.

Is it just me, or did BigWing's second post with his fix somehow get in slightly out of order?:think:

Hmmmmmm......Possibly his other car really IS a TARDIS!8-0=
 

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Is it just me, or did BigWing's second post with his fix somehow get in slightly out of order?:think:
No, not just you, it seems to have appeared as post 3 in the thread and dated 4 days ago. Yet it wasn't there yesterday???
 

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Discussion Starter #15
I wish I'd seen that article about adding the 2 additional wires before I resoldered the base of the post – that's a wonderful idea!
 

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Errrrr....
Which article was this? Link?
I have 3 fuse boxes here I plan on re working this winter.........Love to know what someone has come up with?
 

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Thanks!
An easy mod.
You can still do it as it does not require splitting the boards........
Looking at a fuse board here, and all is exposed, Ya just have to remove the whole mess again, but you should be good at that by now......
Cheers!
 

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I have 2 boards I have pulled and I am looking at from my 2 Rovers. Both have RL9 overheating and pins are starting to get loose. And both seem to have a loose BCM3 power post. I wonder if that caused my lost sync issue on one of the vehicles.
Anyway, for repair what are the best steps to cut or not cut the 32 board to board connectors and add them back? I did not see that in this post, I will look at the Roverworld post now. Or is it just better to buy new or repaired. Does anyone run a repair service for these? Trying to figure out my tolerance for diving further into this mess.
 
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