Getting started in car electrics and was examining my fuse box when I noticed this short wire with a spade connector at each end. Can anyone tell me what it is, what it's for, and if it's some sort of dodgy lash up? The diagram inside the lid says this section of the box is not used.
Its a relay plug, so whatever it goes to has been set to always on
Without knowing make/model we cant say what it is for. there should be a diagram on the underside of the lid
Select to expand quoteTheWolf said..
Its a relay plug, so whatever it goes to has been set to always on
Without knowing make/model we cant say what it is for. there should be a diagram on the underside of the lid
Could be a 'tech note' mod installed by dealer.
Well if it is a relay plug shorted out (so always on) - what stops working when u pull it out? 
Maybe another relay plug buggered up so around the back of the box they are wired together so as to use the vacant position for the first relay, then somebody shorted it out later when the relay itself died??
Select to expand quoteikw777 said..
2003 Toyota Hiace. Diagram says it's a not used section of the box.
Are there any aftermarket items installed? Radio, lights, ect?
Something may have been installed by an installer with a relay and the previous owner decided he wanted it always on
Or something may have been wired through there for another purpose. If it's not an official mod there is little more we can help you with. You will just need to figure it out
It used to have a two-way, and it has an aftermarket stereo installed. Will just leave i alone i guess. Used to be an electricians van so god knows what they were up to.
Select to expand quoteikw777 said..
Is it A/C Fan main? Does it have A/C? I'd say they retrofitted it if it wasn't standard
3rd from right in this picture
Yes it is AC. It looks like you are right. Here's a better pic of mine. I wonder why they didn't want a fuse there? Installed an inline one somewhere else?
Select to expand quoteikw777 said..
It looks like it, here's a better pic of mine. I wonder why they didn't want a fuse there? Installed an inline one somewhere else?
It will be fused somewhere. All they have done is bypassed the control for the aircon fan so that it runs all the time that the van is running instead of running it only when the compressor cuts in.
I wouldn't be surprised if the fan is fused through the 'AC No2' fuse.
The previous owner might have decided that the type of use the van was getting it made more sense to cool it all the time. I guess if it did a lot of slow city work it might have helped.
Select to expand quotelog man said..
I reckon it's ASIO
Holy ****! I hope they haven't been recording my shenanigans!
Select to expand quoteikw777 said..
Yes it is AC. It looks like you are right. Here's a better pic of mine. I wonder why they didn't want a fuse there? Installed an inline one somewhere else?
Cos it aint a fuse its a relay as TheWolf said it hours ago.
And you said the diagram showed it as blank.
Trickey aren't ya.
Select to expand quoteHaircut said..
thermostat (temp sender) for the a/c thermo fan might have died
Usually they don't have a temp sensor for the a/c fan. It switches on with the aircon compressor cycle.
The compressor/fan usually cycle based on pressure switches, but with more modern cars has some computery thing controlling it as well.
Select to expand quoteMark _australia said..ikw777 said..
Yes it is AC. It looks like you are right. Here's a better pic of mine. I wonder why they didn't want a fuse there? Installed an inline one somewhere else?
Cos it aint a fuse its a relay as TheWolf said it hours ago.
And you said the diagram showed it as blank.
Trickey aren't ya.
Guilty as charged.
I think the jumper wire was fitted in the factory.
Not all models of cars, utes, 4WDs etc come with the same options.
In some models the jumper wire would have a relay in that position to operate something which is not fitted to your model.
If you take it out, something will not work, only you might not be aware of what it is.
It could be something as simple as the radiator fan control for the aircon. In australia, it's quite common to have the fan come on as soon as the aircon is turned on. In cold countries they only switch on when things get really hot, and that is done via a relay.
I would just leave it alone,.. well, maybe I wouldn't because my curiosity would get the better of me,.. but it probably wouldn't do me any good to fiddle with it.
Select to expand quotepweedas said..
I think the jumper wire was fitted in the factory.
Not all models of cars, utes, 4WDs etc come with the same options.
In some models the jumper wire would have a relay in that position to operate something which is not fitted to your model.
If you take it out, something will not work, only you might not be aware of what it is.
It could be something as simple as the radiator fan control for the aircon. In australia, it's quite common to have the fan come on as soon as the aircon is turned on. In cold countries they only switch on when things get really hot, and that is done via a relay.
I would just leave it alone,.. well, maybe I wouldn't because my curiosity would get the better of me,.. but it probably wouldn't do me any good to fiddle with it.
Sorry, but I think you are wrong about the aircon fan. I have never looked at the way car aircons work in frozen countries, but generally the fan is to move air through the condensor, and if the aircon is pumping gas through it, there is heat to remove. I doubt it would rely on convection.
I would agree that in a cold country the engine fan might not come on if its too cold, but the aircon is a little bit different.
That jumper wire would not be factory. Manufacturers wouldn't do something like that. If they wanted it permanently on they would hardwire the feed to the relay and not bypass the relay itself. I know on locally made cars that they might have the same fusebox for all models, but they rarely wire up contacts to the fuses and relays that are not needed for that particular model.
I recently rewired a fuse panel to include 'factory wiring' for fog lights and a few other things. The positions are all there, but the wiring is not unless its part of some other circuit and can't be left out.
As I have nothing sensible to say about the actual wire in question, and it appears that the brains trust has established the nature of the wire, I would like to make a general comment.
The conundrum ikw777 faced is the reason that I generally avoid anything that can be considered 'handy'. It has been my experience in the past to tackle all manner of tasks in the expectation that I can fix or improve something. I generally end up with a bundle of confusion and an expensive mistake that needs someone mildly capable of routine skills to fix for me. I now prefer to look, mutter and move away.
It is a symptom of the modern man, but there it is.
Select to expand quoteJulianRoss said...
As I have nothing sensible to say about the actual wire in question, and it appears that the brains trust has established the nature of the wire, I would like to make a general comment.
The conundrum ikw777 faced is the reason that I generally avoid anything that can be considered 'handy'. It has been my experience in the past to tackle all manner of tasks in the expectation that I can fix or improve something. I generally end up with a bundle of confusion and an expensive mistake that needs someone mildly capable of routine skills to fix for me. I now prefer to look, mutter and move away.
It is a symptom of the modern man, but there it is.
Love it.
Select to expand quoteFormulaNova said..
Usually they don't have a temp sensor for the a/c fan. It switches on with the aircon compressor cycle.
The compressor/fan usually cycle based on pressure switches, but with more modern cars has some computery thing controlling it as well.
At a guess, the previous owner of your vehicle might have been having a little trouble with the engine temperature getting a bit high in heavy traffic - so hooked up the A/C condenser fan, or if it has one - an electric thermo fan to run full time.
If your van doesn't have an electrically operated engine fan - and has the silicon oil style of clutch operated fan [when the oil gets hot it engages the fan] the oil may have died and the fan either doesn't come on properly - or engages when the engine is hotter.
It isn't hard to change the silicon oil - and Toyota sell it in tubes for [IIRC] about $17 a tube.
stephen
Select to expand quotesn said..FormulaNova said..
Usually they don't have a temp sensor for the a/c fan. It switches on with the aircon compressor cycle.
The compressor/fan usually cycle based on pressure switches, but with more modern cars has some computery thing controlling it as well.
At a guess, the previous owner of your vehicle might have been having a little trouble with the engine temperature getting a bit high in heavy traffic - so hooked up the A/C condenser fan, or if it has one - an electric thermo fan to run full time.
If your van doesn't have an electrically operated engine fan - and has the silicon oil style of clutch operated fan [when the oil gets hot it engages the fan] the oil may have died and the fan either doesn't come on properly - or engages when the engine is hotter.
It isn't hard to change the silicon oil - and Toyota sell it in tubes for [IIRC] about $17 a tube.
stephen
As far as I am aware the viscous fan comes on intermitently. I can hear it when it does. I will look into this.
Select to expand quoteJulianRoss said..
As I have nothing sensible to say about the actual wire in question, and it appears that the brains trust has established the nature of the wire, I would like to make a general comment.
The conundrum ikw777 faced is the reason that I generally avoid anything that can be considered 'handy'. It has been my experience in the past to tackle all manner of tasks in the expectation that I can fix or improve something. I generally end up with a bundle of confusion and an expensive mistake that needs someone mildly capable of routine skills to fix for me. I now prefer to look, mutter and move away.
It is a symptom of the modern man, but there it is.
Hahhahah funny and very true
I would also add that this thread shows why internet advice needs to be taken with a grain of salt as some posters clearly have not read the question or previous replies. Makes it really hard when you are trying to understand something.
Its referred in the industry as a bridge.
The red wire means its a Positive bridge ( if permanent depending on who has installed it. ) .
Possible that the relay or the circuit is defective someone ( with knowledge) had bridged the positive on the relay for fault finding or for there own beneficial/industry specific reasons. Without the wiring diagram I wouldn't eliminate the car manufacturer. ( could be from motherland.
Just check your master aircon fuse make sure its the right amps. (mabe located under bonnet) and make sure its not been tampered with.
(ac2) ( don't know where ac1 is?) 30a make sure its a 30a and its all good nothing to worry about. (ac not drawing over current)
