Bonnet switch+melted headlight socket

[dom14]

Hi guys,
Vehicle is RB30 Patrol, manual, carby.
I've been going through the electrics of the car(under the bonnet to start with)
with the idea of locating electrical problems with the wiring.
This is my effort to locate some bad wiring or year of electrical wiring wear and tear.
All these is to find and fix bad running issues with the engine, which I've been
suspecting due to electrical problems, as I've been pointed out by the electrical gurus here.

I found two possible candidates under the bonnet.

First is the partially 'cooked' righthand side headlight socket.

Second is an apparently abandoned or ignored bonnet switch, lying pretty close to the headlight socket.

So, your guess is right, I'm indicating a possible connection.

So, I'm wondering.....

1)What is the reason for the headlight socket to melt like that?!
The globes are standard 55W ones.

2)What is the "bonnet switch" for?
Which I'm guessing for a light globe under the bonnet or somewhere else.
Funny thing is that the switch has a spring mechanism to open and close when pressed.
So, when the bonnet is closed, the switch is open
When the bonnet is open switch is closed, which kinda indicates it's for a light globe under the bonnet or something.
But, there's no bonnet light.

I bet there is an RB30 bloke out there who knows what this bonnet switch is for. So, please tell me.

I was also confused by the fact the switch wire was black and it shows +11.65V when I checked with the multimeter.

[dom14]

So, I was confused by the multimeter voltage reading at the apparent bonnet switch wire,
I drew this diagram to sort of 'unconfuse' myself, 'cos I suck at visualization at the moment.
Of course, the actual wiring of this bonnet switch to a possible globe or some other device
may not be exactly as this. But, it helped me to make some sense of the mutimeter reading.
I speculated two possible places for globe, etc in the circuit.
Then my multimeter voltage reading kinda made sense to me.

Now, I'm still wondering what is this switch for and possible reason(s) for the headlight socket melting.

Any help would be great.

Thanks guys.

[Yendor]

Hey mate,

The melted headlight plug is caused by a loose/dirty connection. This generates heat. It's a common problem as the vehicle gets older. Just replace the plug or buy an upgraded headlight wire harness that will come with relays.

The switch is more then likely for an aftermarket alarm. Follow the black wire and see what it connects to.

Your theory regarding the 11.65v is correct. Your drawing not so, you have two bulbs in series when the switch is closed.

I doubt these are causing your running issues.

Cheers Rodney

[Bigcol]

yeppers, what the Master Yendor said

[threedogs]

That looks like an old school bonnet switch.
Have you ran any new earths yet, From what I know Toyo
had earth straps for different sections of the wagon,like
engine bay, dash ,cabin,then motor to chassis and chassis to body.
So I suppose you can never have enough earths.

[dom14]

Hey mate,

The melted headlight plug is caused by a loose/dirty connection. This generates heat. It's a common problem as the vehicle gets older. Just replace the plug or buy an upgraded headlight wire harness that will come with relays.

The switch is more then likely for an aftermarket alarm. Follow the black wire and see what it connects to.

Your theory regarding the 11.65v is correct. Your drawing not so, you have two bulbs in series when the switch is closed.

I doubt these are causing your running issues.

Cheers Rodney

Hi Rodney,
Thanks for the reply mate.
There's an aftermarket alarm in the car.
But, the switch wasn't doing anything, other than hanging, hidden under the windscreen wiper water bottle.
So, I'm guessing it hasn't been doing what ever it is suppose to do for a long time.
BTW, only one of the light bulbs are meant to be there. Positions are hypothetical, as I got no idea about the real placement.
I had trouble picturing it in my head,so I drew the diagram to help my fogged brain.

I think I just replace the headlight plug for the time being.
I'm thinking about replacing headlight globes with LED ones, which apparently draw far less current than incandescent ones.
I'm hoping I can getaway from extensive electrical wiring by doing that way. I hope I'm right about that.
LED replacement for H4 globes are already available. I'm yet to install a one and trial it.

http://www.ebay.com.au/itm/2-X-80W-White-H4-9003-HB2-CREE-LED-Fog-Light-Bulb-1500LM-High-Low-Beam-Headlight-/301611676940?pt=LH_DefaultDomain_15&hash=item463974f50c

http://www.miniinthebox.com/h4-25w-cree-1400lm-5500-6500k-cool-white-light-led-bulb-for-car-12v-24v-2pcs_p893605.html?currency=AUD&litb_from=paid_adwords_shopping&gclid=CK-B-a68kMYCFYcJvAod6kgAiQ

http://www.ebay.com.au/itm/160W-9000LM-CREE-LED-XML-Car-Headlight-Kits-H4-Hi-Lo-Replace-Halogen-Bulbs-6000K-/291490905190?pt=LH_DefaultDomain_15&hash=item43de363c66

I'm guessing cheaper ones among above are only suitable for fog lights, etc.

If I understood you correctly, there's no relay for headlights with the RB30 factory headlight setup.
So, I might have to wire a one if I want less trouble in the future.

Cheers
Dom

[dom14]

That looks like an old school bonnet switch.
Have you ran any new earths yet, From what I know Toyo
had earth straps for different sections of the wagon,like
engine bay, dash ,cabin,then motor to chassis and chassis to body.
So I suppose you can never have enough earths.

Hi mate,
Yep, it's a bonnet switch for sure.
And my gut feeling is that it's been there since the birth of the universe.
I'm just about to follow up the wire and find out what it's for.
I've been cleaning all the old earth wires and replacing the corroded ones.
I will be adding new earths as well.
I added a new stable earth for the tachometric relay(LPG safety switch).
Fairly extensive electrical wiring work.
At this stage, it looks like it's gonna go for a while, as I see crappy old wiring everywhere.
Some of the old and aftermarket conduits are damaged.
Insulation of some wires are so brittle like the wires were covered with automotive body filler.
If I'm allowed, I would replace all the wiring of the car, but just not feasible. :D
You're 200% right, especially when it comes to this vehicle, I can never
have enough earths.
Fair bit of electrical crxp that I've been dealing with so far have been electrical earth issues.

[mudnut]

I hope I am wrong, but
as soon as I read that
your vehicle has had an
after market alarm fitted
I remembered another
vehicle that I worked on.
Nearly all of the wiring
was brittle because the
idiot who fitted the alarm
hadn't wired in a fuse, so
when the alarm failed it
heated up the rest of the
loom. I had to source an
engine bay and under dash
loom and fit and them.
As I said, I hope I am wrong
but it would make sense of
why you've had so many
electrical problems.

[4bye4]

I hope I am wrong, but
as soon as I read that
your vehicle has had an
after market alarm fitted
I remembered another
vehicle that I worked on.
Nearly all of the wiring
was brittle because the
idiot who fitted the alarm
hadn't wired in a fuse, so
when the alarm failed it
heated up the rest of the
loom. I had to source an
engine bay and under dash
loom and fit and them.
As I said, I hope I am wrong
but it would make sense of
why you've had so many
electrical problems.

That was a long post.

[dom14]

I hope I am wrong, but
as soon as I read that
your vehicle has had an
after market alarm fitted
I remembered another
vehicle that I worked on.
Nearly all of the wiring
was brittle because the
idiot who fitted the alarm
hadn't wired in a fuse, so
when the alarm failed it
heated up the rest of the
loom. I had to source an
engine bay and under dash
loom and fit and them.
As I said, I hope I am wrong
but it would make sense of
why you've had so many
electrical problems.

Hi mudnut,
That's a time saving tip you just gave me mate.
I couldn't notice any fuse for the alarm, when I was checking the alarm wiring.
So, it's another area I need to look into straightaway.

This vehicle had been gone through fairly extensive substandard & sometime dangerous backyard electrical work.
The rule says, if a person doesn't have a clue about what he's doing, he needs to get a professional to do the job.
(or learn basics first before fiddling with dangerous stuff)
The idiot who performed the poor electrical work on his own(I'm guessing the previous owner), had done
such a horrible electrical work on it, now I have to go through all the trouble of undoing his crxp.
Since you've followed my previous threads, you know I'm telling the truth.
I'm suspecting even the LPG electrical work was backyard substandard work.
It's a pity, 'cos other than stuffed up electrical work, mechanically the vehicle was on good condition
for it's age and mileage.
When the fuel and ignition system is in tip top running condition, the motor produces a decent amount of torque
for such a tiny motor. Compression, etc is still damn good after I was running with a bad head gasket(and cracked head) for months, few years ago.
Fourth cylinder was covered in rust when I opened the head to do head and the gasket, three years ago.
It's pushing 350k, so I got no major complaints about the mechanics of the car, but the electrics.

Now, I can rev above 4000rpm on LPG and get a decent amount of power to go up hills.
I've never been able to do that before. At least not for a long time.

[mudnut]

That was a long post.

That's because I only
have a 1/4 of usable
screen left after I
accidentally cracked
it with a coffee cup

I am saving up
for another screen.

[Yendor]

Hi Rodney,
Thanks for the reply mate.
There's an aftermarket alarm in the car.
But, the switch wasn't doing anything, other than hanging, hidden under the windscreen wiper water bottle.
So, I'm guessing it hasn't been doing what ever it is suppose to do for a long time.
BTW, only one of the light bulbs are meant to be there. Positions are hypothetical, as I got no idea about the real placement.
I had trouble picturing it in my head,so I drew the diagram to help my fogged brain.

I think I just replace the headlight plug for the time being.
I'm thinking about replacing headlight globes with LED ones, which apparently draw far less current than incandescent ones.
I'm hoping I can getaway from extensive electrical wiring by doing that way. I hope I'm right about that.
LED replacement for H4 globes are already available. I'm yet to install a one and trial it.

http://www.ebay.com.au/itm/2-X-80W-White-H4-9003-HB2-CREE-LED-Fog-Light-Bulb-1500LM-High-Low-Beam-Headlight-/301611676940?pt=LH_DefaultDomain_15&hash=item463974f50c

http://www.miniinthebox.com/h4-25w-cree-1400lm-5500-6500k-cool-white-light-led-bulb-for-car-12v-24v-2pcs_p893605.html?currency=AUD&litb_from=paid_adwords_shopping&gclid=CK-B-a68kMYCFYcJvAod6kgAiQ

http://www.ebay.com.au/itm/160W-9000LM-CREE-LED-XML-Car-Headlight-Kits-H4-Hi-Lo-Replace-Halogen-Bulbs-6000K-/291490905190?pt=LH_DefaultDomain_15&hash=item43de363c66

I'm guessing cheaper ones among above are only suitable for fog lights, etc.

If I understood you correctly, there's no relay for headlights with the RB30 factory headlight setup.
So, I might have to wire a one if I want less trouble in the future.

Cheers
Dom

Yeah the switch needs to be mounted for it to work. Normally when the bonnet is opened that 11.65 volts will be pulled down to zero volts. The alarm unit will then know that the bonnet has been opened and sound the alarm.

Sorry I don't have any experience with replacement LED headlight bulbs but I would be surprised if they worked really well. Maybe someone else can give us a first hand report on theses??

The main things that reduce the performance of the standard lights are

1. Voltage drop at the lights.

2. Faded or dirty reflectors in the lights.

3. Poorly aligned headlights.

The Patrols don't come from the factory with headlight relays.

[Yendor]

That's because I only
have a 1/4 of usable
screen left after I
accidentally cracked
it with a coffee cup

I am saving up
for another one.

What a new coffee cup :)

[mudnut]

I wish! Editted now. Ta, Yendor

[dom14]

That's because I only
have a 1/4 of usable
screen left after I
accidentally cracked
it with a coffee cup

I am saving up
for another screen.

You weren't having a fight about the coffee cup with your misus, were you?! :D
When that happens to me, I usually break her stuff, rather than mine. :coffeetime:

[dom14]

Yeah the switch needs to be mounted for it to work. Normally when the bonnet is opened that 11.65 volts will be pulled down to zero volts. The alarm unit will then know that the bonnet has been opened and sound the alarm.

Sorry I don't have any experience with replacement LED headlight bulbs but I would be surprised if they worked really well. Maybe someone else can give us a first hand report on theses??

The main things that reduce the performance of the standard lights are

1. Voltage drop at the lights.

2. Faded or dirty reflectors in the lights.

3. Poorly aligned headlights.

The Patrols don't come from the factory with headlight relays.

Ok, cool. I'll wire up a relay then.
They are pretty cheap to come by.
It's that I'm bit slack with drawing wires through tight space. :1087:

[dom14]

Bonnet switch is for the security alarm.
So, I reckon I will clean up the bonnet switch and fix it to the bonnet
as it should be.
I also found another wire going towards the rear door(with open ending).
The idiot who wired the security alarm has obviously done a half hearted job.
The wire was taken out of the alarm base unit with pieces of wire sticky taped.
No switch for the backdoor, so it was left just hanging inside one of the
side cavities of the back of the vehicle.

Only thing is that I've already bought an alarm unit separately for the vehicle(while ago)
which I haven't got around to fit in.
The old immobilizer, alarm unit only has one remote key.
Replacement is hard to find.
It's cheaper to buy a new security alarm unit and install it myself.

[dom14]

Here are couple of photos while I was pulling out the carpet near the fuse box on driver side.
One is showing less than half the amount of crap(dirt and soil) I gathered from under the carpet near the corner
(Most of it was sucked out using vacuum cleaner)
Second photo shows the security alarm wire sticky taped(goes towards the rear door),
as well as the rusting caused by soil and water gathering there.
Photo was taken after I fully cleaned up all the crap.
Pretty shocking, I found a water leak and more rust on the passenger side as well.
Water was leaking to the floor from somewhere.
I decided to steam clean the carpet asap.