"razorbeamteam" (razorbeamteam)
06/09/2020 at 18:21 • Filed to: None
2
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"razorbeamteam" (razorbeamteam)
06/09/2020 at 18:21 • Filed to: None | 2
| 7 |
A few months ago the Rover had developed an intermittent electrical fault which I could not track down. The fault caused the whole electrical system to shut off completely and the “audible warning unit” would emit a constant tone until the negative lead on the battery was pulled. I had recently had the dash apart to replace the heater blower motor. I had (incorrectly) assumed that I had a pinched wire, or some other issue which was caused by my work behind the dash. Eventually, it went away and I never looked into it further.
Last week I was driving the truck and it cut out completely and started making the loud tone. Luckily I was coasting up to a stoplight when it happened or else things could have gotten scary.
I immediately went to pull the negative lead on the battery, but noticed that when I bumped the wires coming off of the positive terminal, the tone stopped and everything went back to normal.
This is the literal sad sack of wires that held the 7 fusible links, which provide power to every circuit in the car.
The Range Rover Classic is notorious for electrical gremlins, and many of them can be attributed to this. Apparently, fusible links wrapped up in a fiberglass sock and shoved in an engine bay does not make for trouble free operation. Land Rover realized this, and began installing a proper box when they made the Discovery which containted cartarige style fusible links, which could be mounted in a clean and dry enclosure.
Luckily, I had pulled a box out of a Disco on one of my many trips to the junkyard. It was missing a lid, so they let me have it for da free.
After painstakingly studying the wiring diagram, I was able to map out which links went to which circuits. I then found a reference to the Discovery wiring (which was included on the underside of the lid I didn’t have) and was able to wire everything up. I used some diamond plate I had laying around and only had to drill a few holes to make everything mount up.
The only difference is the Disco box only has 5 spaces for fusible links, but an additional 8 fuse locations. I opted to move over the heated windscreen and an aux circuit to the fuses to match the way the Disco is wired. There are reasons why you don’t want to replace fusible links with fuses, but I figured if Land Rover did it from the factory it’s probably fine. The RRC and the Disco are essentially the same car (sort of like Fraternal twins).
I also wired my ignition box and Hellas through the fuse box and I still have 4 unused for whatever I want to add later.
Now I just need to get a lid and I’ll be good to go. I’m supposed to head out on a road trip starting Thursday so I’m glad the wiring failed when it did.
VincentMalamute-Kim
> razorbeamteam
06/09/2020 at 19:05 |
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There are reasons why you don’t want to replace fusible links with fuses,
What’s a reason you don’t?
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razorbeamteam
> VincentMalamute-Kim
06/09/2020 at 19:12 |
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A fusible link acts like a slow-blow fuse and can handle spikes in amperage above it’s rating temporarily. So if a fan clicks on, or the coil has a high load at high RPM, the spike in amperage won’t cause the link to pop like a fuse would.
If you’re driving down the road and you pop a fuse that controls your ignition or some other critical system, it could be disastrous .
The two circuits I moved were the heated screens and another circuit which contained things like HVAC, sunroof, washer jets, etc. Stuff that doesn’t need to function for the car to still work. I used 30 amp fuses which will hopefully be big enough to handle any spikes from those systems.
DipodomysDeserti
> razorbeamteam
06/09/2020 at 20:20 |
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VincentMalamute-Kim
> razorbeamteam
06/09/2020 at 20:27 |
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Thanks for the detail. They don’t have slow blow fuse with similar characteristics as a fusible link?
I seem to recall that fusible links are usually huge. Maybe they can’t make slow blow fuses that can handle huge amps like a fusible link?
I believe they still use fusible links in modern cars so there must be a good reason a slo-
blo fuse doesn’t work?
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razorbeamteam
> DipodomysDeserti
06/09/2020 at 21:14 |
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I was hoping someone would get the reference.
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razorbeamteam
> VincentMalamute-Kim
06/09/2020 at 23:44 |
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The ones I installed are modern versions. Here’s a close up below. I’m not sure about how modern cars handle the fluctuations in amperage.
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VincentMalamute-Kim
> razorbeamteam
06/10/2020 at 00:11 |
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Thanks. Just looks like a huge fuse. I assume they desi
g
ned
slo-blo characteristics into it
to handle the fluctuations.