BJ40 - no headlights

[craigwanderer]

Hi everyone,

I've got an Australian spec BJ40 which is has a native 12V electrical system rather than the 24V system we see in other countries. I've got no headlights. They went out mysteriously the other day and now the headlights, highbeam and spotlights aren't working.

The blinkers, reverse lights, parking lights, brake lights, tail lights and the instrument lights (apart from the blue high beam indicator) are all working.

Fuses are all good.

Relays are all good.

Bulbs appear all good.

The 40 has hacked wiring. At some stage it had an alarm box in it as well as the old style relays replaced with modern ones. The wiring is not standard but it looks to be a nice, clean job probably done by an auto electrician by the PO.

I don't know if it's related but my 12V cigarette lighter plug is malfunctioning as well. When I was out camping last week I plugged in my 12V laptop power supply to check my email and the 15A fuse in the power supply blew. I replaced it and the same thing - it blew as soon as it was plugged in. Tried 20A and 25A fuses and the same thing happened. Any ideas on what could have caused these problems.

Cheers.

 

[lostmarbles]

Rather a "big ask" here Craig!

I mean you say your wiring is significantly modified! So how can we really tell how its wired or suggest where you should look?

And you tell us you're one of those people who simply put in bigger and bigger fuses when one blows!........ Can I suggest you NEVER AGAIN follow this "fit bigger & bigger fuses tactic"? (The reason should be obvious.)

And why not start by tracking down what's wrong with your cigarette lighter power outlet now? (Buy a cheap multimeter from Dick Smiths to check it out and replace it if necessary. Both things are widely available and cheap.) Then, when you've got that all fixed (with a 15A fuse back there protecting that circuit) - see if your headlights work.

Short Circuits cause fuses to blow. So from what you say - it sounds to me like there could be one of these within your cigarette lighter power outlet. And this will show up (with your new multimeter) as zero resistance between the feed wire (usually red) and the body of the lighter outlet (or its black or green wire - if fitted). But disconnect the thing before testing it.

But maybe I've misunderstood you .....Was it the fuse in your laptop equipment that blew instead of one in your landcruiser? If so - Your decision to fit bigger and bigger fuses there probably cost you a fuse or fusible link in your cruiser and you should realise your laptop (or, if you're lucky, maybe just its power supply) is faulty! So use your muiltimeter to find out where power is being disrupted (in your cruiser). (You'll find "12V to earth" upstream of the blown fuse/fusible-link but not downstream of it.)

 

[craigwanderer]

Thanks for the reply mate. Re: the fuses blowing - these were removable fuses in the laptop power supply itself. It was not connected to the laptop at the time.

No landcruiser fuses were harmed in the making of this post.

I picked up a new multimeter this morning which I guess I'll have to use after I've untaped the wiring harness from the headlights to the switch to the battery, something I want to avoid doing if at all possible. I was hoping for a quick fix that would see me being able to drive my daily driver at night again using the headlights as fitted to the vehicle. Is it possible that the light switch is stuffed?

I am not good with auto electrics, but I am trying to learn the vehicle's systems so that in time, I will be able to diagnose and fix things like this for myself. Seeing as the wiring under the dash next to the hand throttle is non-standard, I'm at a loss, but I don't want to take it in to an autoelectrician who will most likely fix the problem in 15 minutes, but not necessarily show me how it happened in the first place.

Thanks for your help.

 

[lostmarbles]

...Re: the fuses blowing - these were removable fuses in the laptop power supply itself. It was not connected to the laptop at the time. .........

Ooops. I obviously misunderstood which fuse you were referring to Craig. It looks like your laptop power supply must have a short (or be completely knackered). But who cares! It is the cruiser that matters!

...... No landcruiser fuses were harmed in the making of this post...........

Phew. I can hear collective sighs of relief from where I sit!

.... after I've untaped the wiring harness from the headlights to the switch to the battery, something I want to avoid doing if at all possible. ....

Sounds like you mistrust the wiring done by the PO to consider doing this!!!

I heard someone mention some time back that early cruisers have "dodgy spliced joints" hidden deep in their wiring looms but I wouldn't expect that to apply to our BJ40s. (So normally I wouldn't expect us to have to do any of that sort of thing to uncover electrical faults!)

........Is it possible that the light switch is stuffed? ...

Anything is possible. Your cruiser is 30 years old. but having said that - those switch are made-to-last.

To be honest, the FSM wiring diagram isn't really that much help (even ignoring the fact that your wiring has been modified). I use it only as a rough guide for my BJ40 - I say this because I have found my as-built wiring differs quite a bit from any drawings I've ever seen.

But using the 1981 diagram (and common sense - hopefully) as a guide, I'd check for 12V:

• At connectors either side of your fusible links, then
• Either side of the 15A headlight fuse on your fuse panel, then
• At your headlight on/off switch
• At your high/low beam switch (dip-switch), then
• At your headlights

Most of these are easy enough to reach.

The fourth would involve removing the plastic covers off your steering column (not really hard).

And as for the last - I doubt you would be getting power that far without your headlights working (unless their is a problem with their "earthing").

Of course you should realise that the frame and bodywork are used as "earthing paths" (just the same as wires are) to carry the current back to the negative terminal of your battery.

And things are "energised" (and should "work") when there is a COMPLETE circuit through them that links both sides of your battery. (So autoelectrics isn't that difficult to fault-find.)

Hope this helps Craig.

 

[craigwanderer]

Wow Tom, your setup is nice and clean.

Here's mine:

Thanks very much for your help mate. Your advice has been invaluable - it's given me a starting point to work from.

Now that I've got the canopy on the Gecko mostly repaired and sorted I'll have another go at the electrics tomorrow morning before I fix the metal sections of the heater hose - the pipes that go through the firewall have both got pinholes in them, identified by a puddle of green coolant under the driver's side floor mat.

Cheers,

Craig

 

[craigwanderer]

Having fixed the heater hoses, I'm about to start troubleshooting the electricals. Is a fusible link on one of these a small plastic box with two glass fuses in it? If so, they are all good. I've also got two inline fuses running off the battery and these are good too. I can't find any modern fusible links (looks like an overgrown fuse), so I'm guessing the little plastic box is it.

I'm about to remove the instrument cluster so I can check the plugs on the back of the light switch and to have a look at why my ammeter isn't working at all. I'll also have a good look at the cigarette lighter/accessory port and see why it's blowing fuses in stuff. I checked it with a cupholder USB/12V accessory adapter and it blew as well. Funnily enough, a fluorescent work light plugged into the cigaretter lighter port works fine. Go figure.

I'll have another stab with the multimeter and report back in case someone else has the same problem down the track. I love ih8mud.com, it's one of the best references out there on automobiles on the internet period.

 

[lostmarbles]

.. Is a fusible link on one of these a small plastic box with two glass fuses in it? If so, they are all good. ....

From what you describe - that black box contains your 5 amp ammeter fuses. (They're just there to protect your ammeter.)

...I've also got two inline fuses running off the battery and these are good too....

I'd say your PO replaced your original two fusible links (BJ40) with these. What sizes/ratings are they?

...I'm about to remove the instrument cluster so I can check the plugs on the back of the light switch and to have a look at why my ammeter isn't working at all.....

I think I can explain why your ammeter isn't working.

Your ammeter is designed to be driven off the voltage drop across one of your fusible links. (Which is why those two 5A fuses are meant to connect to either side of this particular fusible link.)

But since your PO fitted an inline fuse there instead - you'll probably never see your ammeter needle move again. The PO's fuse is probably sized too large to create the necessary voltage drop. And even if it was sized better/smaller - it is doubtful it could ever perform in the same way as that fusible link did.

...I'll also have a good look at the cigarette lighter/accessory port and see why it's blowing fuses in stuff.....

I thought you established that the fault was in your laptop power supply and not in the cigarette lighter power outlet

...I checked it with a cupholder USB/12V accessory adapter and it blew as well. Funnily enough, a fluorescent work light plugged into the cigaretter lighter port works fine. Go figure....

Where was this fuse that blew? In the USB adapter?

 

[craigwanderer]

Thanks again Tom, I'm about to go and take photos of the spaghetti under the bonnet next to the battery, but before I do, I'll get back to the cigarette lighter issue again...

The fuses in the 12V plug-in accessories (laptop power supply and USB/Double Accessory adapter) blew I believe because they were overloaded from the cigarette lighter port. It was odd that the Fluoro work light had no such problem. This afternoon as I got out of the vehicle, I received a small electric shock from the side of the tub - I'm thinking I've got a short circuit somewhere and hopefully this is where both the headlights and cigarette lighter problems stem from.

I'd still like to work it out rather than take it to an auto sparky, in case something similar happens again.

To be continued...

 

[craigwanderer]

I found a pic in another thread showing the fusible links on Tom's BJ40 -

It certainly looks the PO has replaced mine with fuses:

Both are 20A fuses and are in good condition.

Here is the fuse box for the ammeter - fuses are both corroded and I get no volt reading either side of them.

Before I continue, there are a couple of mystery plugs that I have been unable to ID:

First ones:

These are on the same side as the battery near the firewall.

Second one:

This one is part of a system that goes from the alternator to the engine as shown. Only one is plugged in, is this normal?

I do not know if this is related to the lights/cigarette lighter, but when I remove and replace the battery lead, the blinkers flash.

I checked the indicator switch and the clicking doesn't come from there, instead it comes from this box:

It appears to be some sort of alarm control box.

I removed it and the indicators stopped flashing by themselves. They and the hazard lights still work via their respective switches.

Back to the cigarette lighter...

I checked it visually and it all looks OK:

But I'm going to have to remove the radio or the heater to get to the back of the dash.

Here are the two accessories it blew fuses on:

Laptop Power adapter (with 20A test fuse still in place and blown)

Cupholder USB adapter (fuse is in the plug itself):

For what it's worth, I touched the tub near the door latch and received a small shock - Both feet were on the running boards at the time

 

[craigwanderer]

But using the 1981 diagram (and common sense - hopefully) as a guide, I'd check for 12V:

• At connectors either side of your fusible links, then
• Either side of the 15A headlight fuse on your fuse panel, then
• At your headlight on/off switch
• At your high/low beam switch (dip-switch), then
• At your headlights

View attachment 358365

Forgot to say -

12V appears at either side of the 15A headlight fuse in the fuse block.
12V appears on the headlight switch - all modes except "off".
12V apears either side of the fuses the PO has used to replace the fusible links.
12V does not appear either side of the ammeter fuses.
12V does not appear at the headlights.

 

[lostmarbles]

.... The fuses in the 12V plug-in accessories (laptop power supply and USB/Double Accessory adapter) blew I believe because they were overloaded from the cigarette lighter port. It was odd that the Fluoro work light had no such problem. .....

I'm having trouble with this.

I can't imagine any fault within your cigarette lighter capable of blowing fuses in your accessories Craig.......Unless somehow your lighter outlet is supplying those accessories with voltage in excess of 15 volts!

..This afternoon as I got out of the vehicle, I received a small electric shock from the side of the tub - I'm thinking I've got a short circuit somewhere and hopefully this is where both the headlights and cigarette lighter problems stem from....

Well this tends to support the idea that maybe youré getting some high voltage somehow.

I believe your battery voltage is really too low to be capable of giving anyone a shock in this way.

Perhaps static electricity is present? (From wool seat covers?)

Or.....You don't have anything plugged into the mains and connected to your cruiser (eg. a battery charger) that may be faulty and posing a risk of ëlectric shock"?

.... It certainly looks the PO has replaced mine with fuses..... Both are 20A fuses and are in good condition.... Here is the fuse box for the ammeter - fuses are both corroded and I get no volt reading either side of them.....

Those small-gauge wires you see on your fusebox ....Can you see if they connect to either side of one of those 20A fuses.

My guess is that the PO left the ends dangling somewhere. (At least that would explain the lack of voltage at the fusebox anyway.)

... Before I continue, there are a couple of mystery plugs that I have been unable to ID....
These are on the same side as the battery near the firewall. ...

Do you have an EDIC system fitted? (Electric Diesel Injection control)

My guess is that those plugs are meant for an EDIC motor.

...Second one:..... This one is part of a system that goes from the alternator to the engine as shown. Only one is plugged in, is this normal?...

I can't see very well on this computer at work. But if it is the group of wires I'm thinking of - One goes to the "oil pressure gauge sender unit" and the other is for the "low oil pressure cut-off switch". But if you have no EDIC motor - you probably don't have that switch fitted either.

.... I do not know if this is related to the lights/cigarette lighter, but when I remove and replace the battery lead, the blinkers flash. .... I checked the indicator switch and the clicking doesn't come from there, instead it comes from this box.... It appears to be some sort of alarm control box.... I removed it and the indicators stopped flashing by themselves. They and the hazard lights still work via their respective switches....

I think you hit the nail on the head Craig - In other words, I think it is an aftermarket security system that the PO has fitted.

... But I'm going to have to remove the radio or the heater to get to the back of the dash....

Good luck. I've been upsidedown with my head under my dash before (and my knees hooked over my bench seats) and its certainly not pleasant!

...Forgot to say - ..
12V appears at either side of the 15A headlight fuse in the fuse block.
12V appears on the headlight switch - all modes except "off".
12V apears either side of the fuses the PO has used to replace the fusible links.
12V does not appear either side of the ammeter fuses.
12V does not appear at the headlights.

The headlight switch should have a number of terminals. So I'm a little confused by what you are saying about it here. (Doesn't it control your sidelights as well as your headlights?)

Just as a random thought - Can you get your headlights to flash by pulling your headlight dipswitch lever towards you?

 

[rockcrawler]

With the cig lighter one possible explanation is that its wired opposite, i.e. negative where there should be positive. Cig lighter will be happy with this but not electronic circuits. Fluro light probably won't care either way. You might want to test both those things that blew fuses out at a reliable source to see if they are still working.

I must say what a damn mess with the wiring! Even if there was a major short in there when it was replaced, why replace the whole thing and turn it into a nightmare only the person having wired it could understand... well perhaps not even them!

 

[Coolerman]

I concur, the lighter plug is wired backwards.
That alarm box possibly may have been wired to flash the headlights when the alarm sounds. If you can trigger the alarm, and the lights do flash, you know it's in the headlight switch or wiring between the switch and lights.

Before you hire a voodoo priest to fix your wiring do some simple things first.

Disconnect the battery: then one at a time, pull ALL the fuses from the fuse box. Using a Dremel tool with a wire brush or some fine steel wool, clean the fuse holder clips to bare metal. Carefully bend them in just a tad to help hold the fuses in place better. Also clean the ends of the fuses and TEST each fuse BEFORE you put it back. It may look good but still be bad.

Clean the battery terminals at BOTH ends. Especially the frame ground.
Charge the battery if the measured voltage is below 12.4 volts. This ensures everything will get full power for testing.

Pull a headlight connector. Turn on the headlight switch. You should have +12V on ONE of the terminals. Hit the dimmer switch. The other terminal should have +12V. The ground terminal (It's white/black) should be a dead short to ground. Set your meter to read low ohms and read between the ground wire and the negative battery terminal, it should read very low like 0 to 2 ohms.

That should get you started....

Good luck!

 

[lostmarbles]

I've just noticed from Craig's signature line that this BJ40 has been molested in a big way! So no wonder it doesn't have an EDIC motor or Low Oil Pressure Switch............. It actually has a 13B motor rather than the original humble-B!

With the cig lighter one possible explanation is that its wired opposite, i.e. negative where there should be positive. Cig lighter will be happy with this but not electronic circuits. Fluro light probably won't care either way. You might want to test both those things that blew fuses out at a reliable source to see if they are still working....

I concur, the lighter plug is wired backwards.....

I would have thought this was impossible myself?

Wouldn't that cause the outer body of the cigarette lighter outlet to immediately shortcircuit to the dash panel (when the PO was fitting/wiring-up this accessory).

..That alarm box possibly may have been wired to flash the headlights when the alarm sounds. If you can trigger the alarm, and the lights do flash, you know it's in the headlight switch or wiring between the switch and lights.

Before you hire a voodoo priest to fix your wiring do some simple things first.

Disconnect the battery: then one at a time, pull ALL the fuses from the fuse box. Using a Dremel tool with a wire brush or some fine steel wool, clean the fuse holder clips to bare metal. Carefully bend them in just a tad to help hold the fuses in place better. Also clean the ends of the fuses and TEST each fuse BEFORE you put it back. It may look good but still be bad.

Clean the battery terminals at BOTH ends. Especially the frame ground.
Charge the battery if the measured voltage is below 12.4 volts. This ensures everything will get full power for testing.

Pull a headlight connector. Turn on the headlight switch. You should have +12V on ONE of the terminals. Hit the dimmer switch. The other terminal should have +12V. The ground terminal (It's white/black) should be a dead short to ground. Set your meter to read low ohms and read between the ground wire and the negative battery terminal, it should read very low like 0 to 2 ohms.

That should get you started....

Good luck!

I know nothing about security systems and I guess the previous owner hasn't briefed Craig on it (and that he hasn't been given a "remote" for it or anything).

I was wondering if maybe the secutiy system itself could be responsible for the headlights not working somehow?

 

[craigwanderer]

Hi guys, thanks very much for all your effort in helping me track down the problem. As of this afternoon, I have followed all of the suggestions put forward here and in this related thread: https://forum.ih8mud.com/40-55-series-tech/265778-head-lights-went-out-tonight.html , but to no avail. The bitch still isn't lighting up. On the flip side though, I have become very familiar with the electrics in my vehicle and should be able to diagnose and trouble-shoot any lesser problems I may encounter in the future.

I've booked the car into the voodoo magic man in the morning and I was able to negotiate with the autoelectrician to be basically looking over his shoulder the whole time. I spend about half the year in a remote area for work (Cape York Peninsula - the pointy bit of Australia), where apart from two far-flung regional centres there are no auto electricians or roadside service available. That was enough to convince the auto sparky to let me watch him work. If he does a good job, I might even throw him a bone and let him install my dual battery set (I know how to do that in theory).

I'll report back tomorrow with what caused the problem and what the solution was.

Thanks again.

Cheers,

Craig

 

[lostmarbles]

Wow. Getting paid for being in the Cape York area! I should try and get into your line of work and hop over there!

(It's still on my agenda to explore that area - but purely for pleasure.)

I'll be very interested to find out what turns out to be your problem.

I'll bet it will be something you'll want to kick yourself in the butt for overlooking. (That's usually the way it turns out. )



PS. If you PM me your Email addy I can send you the FSM 1981 BJ40 wiring diagram but IMO it is mostly bullsh#t as far as our headlight wiring goes. It seems to concentrate on the crazy Canadian 24V headlight set-up where they apparently use 12V headlight bulbs.

 

[craigwanderer]

Just got the vehicle back from the auto leckie. The poor bastard looked a little uncomfortable with me peering over his shoulder the whole time. He kept asking me if I was going to be late for work and if I wanted to organise the courtesy car. I'm a writer and work from home base for half the year, so there was a visible shoulder slump when I told him I had all day.

The PO had installed an alarm, but as you can imagine, in a soft top 40 the alarm would constantly go off when the vehicle was parked whenever a truck rumbled past or if there was a big gust of wind. Accordingly, the PO removed the alarm itself, but not the control box. There was a fault in the alarm control box which was resulting in the headlight fuse blowing. Having checked the fuse block and the fuses and with them being A-OK, I didn't think to check the fuse again after I had cleaned the terminals and reistalled the fuse. When I would install a new fuse, turn the lights on and then get out of the vehicle to visually check the lights were working, the fuse blew while I was walking around to look and I was none the wiser.

The fact that the fuse blew under the end cap and looked OK visually was just a rimshot tacked onto the end of this comedy of errors.

The Voodoo Magic Man played with the alarm control box lead and I believe he linked and/or terminated a couple of the wires to ensure the problem wouldn't recurr. I've learned a valuable lesson - check and double-check electrical problems. If I'd known that the headlight fuses kept blowing, it would have saved a lot of time rather than trying to diagnose the whole headlight system from the lights to the battery to the switch.

The cigarette lighter issue was tracked back to an apparent short in my laptop power supply. It's not wired arse-backwards. I'm not happy with this diagnosis because it doesn't explain the other accessories blowing their fuses. As a quick fix, I'll be plugging the laptop power supply into the cupholder adapter so it's protected by the two fuses. If it happens again, new laptop power supply.

Once again, thanks for all your help.

Cheers,

Craig

PS: lostmarbles, in conjunction with a Cairns-based tour operator I take tourists through some of the WWII military bases and aircraft crash sites up on the Cape as well as do heritage survey stuff for the QLD parks and wildlife service. It's quite interesting. I get to mess around in Iron Range Nat Park, Portland Roads, Cooktown, Princess Charlotte Bay, Bamaga, Seisia, Atherton Tablelands, Lakefield Nat Park, spend a bit of time in Weipa and Arakun, etc.

I've got the 1981 FSM wiring diagram. Why the hell did they think that a 24V system with 12V headlights would be a good idea? I think the Aussie market had the right idea - "go full 12V or we won't buy it".

 

[rockcrawler]

Me and Tom have been discussing the workings of the ammeter circuit in private and I would like to share the conclusion with everyone.

So Tom... we were both wrong

You for thinking that the fuses were anything other than a fuse (as far as functionality), and me for thinking the circuit required a shunt. But the thickness of the wires going to the ammeter should have told you it is taking the full amperage Tom

I had a look at those fusible links and there is no way they could make up a shunt. So I ended up pulling my cluster to bits just to prove to Tom that there is indeed a shunt resistor across the gauge terminals inside the cluster. But there isn't one as none is needed. The ammeter gauge is not the standard type "moving coil" type, in fact there are no coils or springs in it. These type of ammeters are not so common and but they still work on the principle of a magnetic field influencing the movement of a needle.
With common type ammeters the coil provides some damping to the needle movement but with these there is no damping and they tend to be jittery.

 

[lostmarbles]

Me and Tom have been discussing the workings of the ammeter circuit in private and I would like to share the conclusion with everyone.

So Tom... we were both wrong

You for thinking that the fuses were anything other than a fuse (as far as functionality), and me for thinking the circuit required a shunt. But the thickness of the wires going to the ammeter should have told you it is taking the full amperage Tom

I had a look at those fusible links and there is no way they could make up a shunt. So I ended up pulling my cluster to bits just to prove to Tom that there is indeed a shunt resistor across the gauge terminals inside the cluster. But there isn't one as none is needed. The ammeter gauge is not the standard type "moving coil" type, in fact there are no coils or springs in it. These type of ammeters are not so common and but they still work on the principle of a magnetic field influencing the movement of a needle.
With common type ammeters the coil provides some damping to the needle movement but with these there is no damping and they tend to be jittery.

Ooops. My fault Alex. - I forgot yours is a 1977 model.

In fact yours is the old style where all your current (amounting to tens of amperes at times) does pass through your in-dash ammeter.

Craig's and mine are both the more modern style that use one fusible link as a "shunt resistor" to drive much smaller currents (milliamperes) through a much-more-delicately-wound ammeter.

I think the changeover year must be 1978.

So that explains why your ammeter needle moves properly too.

Cheers
Tom

PS. I'll try and remember to send you the wiring diagram for my-style of ammeter Alex. (Tomorrow morning when I get back home). And thinking about it more - you probably were never given any fusible links AT ALL on your model.

And it is good to see you got your problem fixed Craig. (I knew you'd want to kick yourself!) And I envy you with your job that gets you into such fantastic parts of Oz!!

 

[rockcrawler]

Still makes not much sense to me. If that fusible link is indeed a "shunt" then if it blows it will send all the current through your gauge. Remember a shunt is in parallel not series.