7 replies to this topic

[Mini-Hazel-Nut]

Good evening all, I have a problem, nothing new there. If I can refer you to the blue Haynes manual for Mins 1969 to 2001, page 12A-35 there is a wiring diagram. Item 5 is the lighting switch and there is a brown wire that goes to an inline fuse which is item 48. I`m pretty sure I blew this fuse the other day which may explain why I have no lights. Thing is does anyone know exactly where I`ll find this fuse? I`m sure I heard the darn thing pop but I don`t know where it is. Any help greatly appreciated, thanks.

[Tornado99]

Unsure of what year/mark  of car you have. but the wiring diagrams I've looked at in the Mini Haynes manual do not usually place items like fuses in their relative locations next to components they affect. So an "in-line" fuse in the diagram may actually be sitting in the fuse box no where near the lighting switch or bulbs it protects. 

 My '88 car has four fuses in the fuse panel box, in engine bay firewall. One fuse has the lighting circuit plus other items protected....so if it blows, several different things are affected. On the wiring diagram this fuse is shown at some random place where it was convenient to draw for clarity on the diagram.

 

Generally, you will not heard a fuse blow. Maybe you have a relay fitted by a previous owner between the light switch and the powered line and you can hear that clicking? 

Edited by Tornado99, 02 February 2021 - 07:06 PM.

[Ethel]

A single fuse wouldn't be responsible only the latest cars had fuses on the headlights & then the two sides are fused independently, specifically so one fuse blowing can't suddenly leave you in darkness.

 

There is a fuse for the side/tail lights, in the fusebox.

 

The fuse you mention is for the interior light, brake master cylinder warning, horn & headlight flasher. If any of those work the fuse ain't blown.

 

Let us know what exactly isn't working.

[Mini-Hazel-Nut]

My car is a 1986 Austin Mini according to the V5. After ermoving the tatty full width dash I found an enormous jumble of badly connected wires to do with the radio I removed a lot of this mess as radios don`t interest me. The lights were working at that point. It was just after I installed the heater and associated piping and trunking (none these installed when I bought it) and was tidying things I hear a pop somewhere in the depths of the dash and then the lights failed to work as did the rear screen heater which I had just plugged back onto its switch as it had been left off. The four fuses in the engine bay are still in one piece and I am flummoxed as to where to look for the fault. Where the wires leave the steering column many of them had been tapped into by a previous owner(s) leaving the whole set up a right mess with very difficult access as I`m sure you all know.

[Tornado99]

You will need a test lamp to poke around at various locations to find these kind of faults. You can make one up with two lengths of wire and a little 12v light bulb. I like the cheap automotive test lamps, with a sharp spike probe one end, aligator clip at other. Mine is a more modern version using an LED light that goes red when probe sees positive voltage, green when it sees negative volts. Extremely helpful for this kind of work. 

Edited by Tornado99, 02 February 2021 - 08:56 PM.

[Mini-Hazel-Nut]

Thanks all. Looks Like I`ve got to bite the bullet and strip all the dash again tomorrow, can`t see a damn thing at the moment. I`ll let you know if I find anything.

[Ethel]

Still not clear exactly which lights are out.

 

Does the interior light, or horn, or brake test switch work?

 

Do you have dash illum & sidelights?

 

Headlights dip & main?

 

Headlight flasher?

[cal844]

In the Haynes manual diagram 16 and 17 is for 1984 onwards carb models (16 is single instrument pack, 17 is multiple)

The line fuse is on a brown wire, which comes into a line fuse (wire originates from starter) which suggests to me to be a main fuse (fuse box).

The brown wire from the starter is fused (Iirc fuse #2 on main box) before it goes to the headlight switch.


Now you need to check the fuses in the fuse box (take each one out and try to twist the ends in opposite directions. (if it twists its scrap, replace it with new).
By the looks of the diagram it'll be a fuse here. Either on the Brown wires (#2fuse)

If the fuse box checks out ok make sure there is no inline fuses behind the carb or under the dash inline fuse plastic holders will burn out and give problems you describe.

I'd highly suggest buying a power probe. Itll make fault finding easier

https://www.amazon.c...479303029&psc=1

I have one with the screen so you can do voltages.

I hope this helps somewhat,

Regards

Cal

Edited by cal844, 02 February 2021 - 10:33 PM.