Thread: What are these?

Originally Posted by Dervish

Sorry I'm late to the party. Chris, just leave the "fuse" out. That little "fuse" you found is actually a fusible resistor, it is usually a part of the operation of the warning light. Looking at the schematic now it looks like it is not an essential part; I think perhaps it is a part of the V8 harness and redundant with the W/LT relay and 3 pin alternator as used with the 4BD1. In an older alternator setup, the warning light also functions as the IGN feed; the resistor provides an alternate source if the bulb blows.

Replacing the fusible resistor with a fuse will always result in the fuse popping, unless you use a really large fuse.

Oh, W/LT is warning light. The relay disconnects the warning light from earth once the alternator comes online.

As the schematic says, the resistor should probably have been removed at the assembly line. I'll check if mine still has the fusible resistor there one day. Bottom line is, it isn't doing any harm being there (except getting warm).

THANK YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

You are awesome!

Is that heat something you would expect from such a thing?
and getting hot only when ignition on but not started, would that be what you would expect?


It would be very much worth checking your vehicle to see if they are in there. If left for more than a minute, it gets too hot to touch.
I really cannot understand why/how it had not caused a fire to be honest.

To check, remove the instrument binnacle and shine a torch down the bottom left , you will see the fuse holders down there. (maybe, mine were covered in mud and underneath the main harness - very hard to see)


I was hesitant to unplug it just in case that stopped something from working though would cause something to fail. It seemed weird that something that is obviously pulling power could be disconnected without disabling something.

Thanks again!

<edit> I'll hit you up next time I'm up the coast. I owe you a beer

Originally Posted by Chris078

Is that heat something you would expect from such a thing?

Yes, it is basically a light bulb that doesn't light up so it will get to a similar temp.

Originally Posted by Chris078

and getting hot only when ignition on but not started, would that be what you would expect?

Yes, power is supplied to both the light and the fusible resistor via the AUX position on the ignition switch. They are both then earthed through a NC relay (the warning light relay) that is fed switch signal from the alternator output. Once the alternator is generating the warning light relay opens; the circuit is disconnected and so the fusible resistor and the warning light both cool down.

Originally Posted by Chris078

<edit> I'll hit you up next time I'm up the coast. I owe you a beer

Any time

I'll get up there one day Dervish!
Thanks for the advice.

I got the electrics back together and taped up again today.
Everything works, which is nice.
Will put the dash back in on the weekend.

What are peoples thoughts on spaying some oil (fisholene/lanolin) into the holes to coat the inside of that hollow, inaccessible part that runs along the top of the Firewall, just below the vent flaps?

That seems to be where many Landies rust out, and since I have everything out, if there is something I can do to protect that area, I may as well do it.

Originally Posted by atwood

Ignition w/lt surely has to be the ignition warning light.
Sounds like when your ignition warning light is on (or is supposed to be on), your mystery item tries to ignite your vehicle.

Work light probably. The red and black sockets

Originally Posted by LieutenantRover

Work light probably. The red and black sockets

It's the Battery Warning light.
It's for that little battery light in the instrument panel.
This relay is one of the two on the firewall up behind the brake booster.

I have no idea what the other relay is. I suspect it has something to do with the blackout lights.

Also may have found the source of my original (shorted wire) problem
Noticed one of the relays in the fusebox was getting very hot. The one that the shorted wire was originally attached to.
Popped on a spare Narva relay which remained cool.
The one I took off was dated 1989. The others are as well, so a trip to Supercheap is order to replace the rest on the weekend.

Originally Posted by Chris078

I'll get up there one day Dervish!
Thanks for the advice.

I got the electrics back together and taped up again today.
Everything works, which is nice.
Will put the dash back in on the weekend.

What are peoples thoughts on spaying some oil (fisholene/lanolin) into the holes to coat the inside of that hollow, inaccessible part that runs along the top of the Firewall, just below the vent flaps?

That seems to be where many Landies rust out, and since I have everything out, if there is something I can do to protect that area, I may as well do it.

Just to clarify, what do you mean by taped?

Just to clarify, what do you mean by taped?

Taped, as in taped the loom up again. Had to remove all the tape that holds it in a bunch in order to trace where things go.
Don't worry, I didn't use electrical tape (though the factory did) i bought some proper fabric wiring harness tape.