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Additional Fuses

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M

mgtf328

Jedi Hopeful
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I'm trying to work out what fuses I should add to my BJ8.
It seems to me the following items are already fused through the original '2 fuse box' :- Horns, Fuel Gauge, Heater Fan, Stop and Tail Lamps, Fuel Pump and Wiper Motor. Can someone please tell me whether this is correct/adequate as my electrical expertise is very low!

I have added a 10A (UK) fuse to the indicator/4 way flasher units and a previous owner added some lighting relays and converted the lights to halogen/LED and added two fuses.
Are there any other circuits I should fuse? If so what size fuse would you recommend?
Additionally, my BJ8 wiring diagram which shows a fuse in the line to the license plates. Does anyone know where this fuse is located as I can't find it on my car.

Regards from windy,rainy, cold Gloucestershire in the UK
AJ
 
AJ--

I'm sure you'll get a lot of advice as opinions certainly differ on the matter of fusing circuits, but I am one of those that feels each appliance deserves its own separate fuse of the proper value relative the current it carries. Yes, the components you list are protected--at least in theory--but the concept is to guard against damage to both the appliance and the wiring to and from it by providing a fuse of appropriate amperage. Using a 50 amp fuse to protect 18 or finer gauge wiring might not be too much better than using a 16D nail, or no fuse at all.

I installed two multi-position fuse panels--one for items that are energized through the ignition switch such as the windshield wipers, fuel pump, etc. and another for items that are hot all the time such as the horn, lights, etc--and installed fuses of a value appropriate to each item's load. If in doubt with what the proper fuse should be I start with a lower value fuse and should it blow I can move up a step once I determine what was the source of the failure.

If you are concerned about maintaining an original appearance you can install the new fuse panels in a concealed spot such as on the interior side of the firewall and leave the two-fuse panel and wires to it in place, cutting the wires in an inconspicuous spot for feeding to your new fuse panels.
 
I believe the idea behind adding fuses is to segregate the components so that instead of having multiple things running through one fuse you work toward a dedicated fuse for each component. As for the license plate light, there may be an in-line fuse hidden beneath the boot lining.

Jack
 
The upper fuse in the original fuse box serves five circuits: Turn signals, fuel gauge/tachometer, brake lights, heater blower, windscreen wipers.
The bottom fuse serves the horns.

Having had a problem with the upper fuse blowing and determining which of the five circuits was causing the problem, I decided to break out the circuits served by the upper fuse into individual 20A fuses, with the additional fuse box under the dash. Since then, it has been easy to find the problem circuit without a lot of troubleshooting. To avoid cutting into my fairly new wiring harness, I made all the connections with jumper wires so that the original wiring is left intact. The original upper fuse in the box now serves only the heater blower.

Although the wiring diagram does show a fuse for the rear license plate light, my BJ8 did not have that fuse until I installed a 10A in-line fuse for it inside the boot.



AJ, you have a private message.
 
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