4x4 auto electrics

[nucopia]

Ok so i finally have my landcruiser on the road but it still has a few small issues with the electrics
Since I bought it I have had to replace the wiring harness to the knock sensors , replace a CV joint and do a few other mechanical repairs. It looks like the last owner had a lot more things connected i.e driving lights/fog lights and I suspect a secondary battery. It has a few wiring harnesses under the bonnet that lead to nothing.

It came wth a Uniden UHF radio that never worked. Today i disconnected the power and earth wires to check if it was getting power and it wasnt.
I tried to trace the wires back to the power source to see if there was a fuse problem or a loose connection.
Boy did that open up a can of worms under the dash.
Seems the last owner had a black widow alarm system connected under the dash and wires are running every where.... luckily some one must have unplugged the male to female wiring harness and removed in line fuses ro what ever Was wired through the alarm system is not working , kill switch UHF radio. And who knows ?

Right now all the standard accessories have power ..Radio dome lights dash lights CD/radio cig lighter map lights etc etc .
Only the conection to the UHF radio is not getting power.
I am wondering , should just by pass the old wiring ( it leads to the disconected alarm system) and connect it directly to the battery or should I tap into another power and earth circuit and run it off say the same circuit as the radio or cigarette lighter or some thing else ?

I bought a multi meter, a role of red and black electeical wire, crimpers , a box of assorted cable conections fuses etc a roll of silver solder and a soldering iron.
What i dont have is a lot of knowledge.

 

[blisters]

I'd put in a dedicated fuse block for your accessories like:

http://www.jaycar.com.au/Passive-Co...Blade-Fuse-Block-with-LED-Indicators/p/SZ2008

That way you know that what is added and wired up is good and fused properly. Sounds like you have to de basterise your wiring from the previous owner I wouldn't have a lot of confidence with loose ends rattling around.
Jon

 

[nucopia]

I'd put in a dedicated fuse block for your accessories like:

http://www.jaycar.com.au/Passive-Co...Blade-Fuse-Block-with-LED-Indicators/p/SZ2008

That way you know that what is added and wired up is good and fused properly. Sounds like you have to de basterise your wiring from the previous owner I wouldn't have a lot of confidence with loose ends rattling around.
Jon

Thanks blisters
I think your right, I might need to seek the help of a friend with more experienced them my self as its a little daunting .
I really wanted to learn how to do things my self with out damaging anything or imposing on friends. But I may not have much choice.
The mate I spoke with today also suggested getting a dedicated fuse block and taking out the redundant wires.
His the one that gave me a list of what essentials I needed to buy to get started , i just forgot to,buy the fuse block.
I might take him a bottle of bourbon and see if he can help me with it over the next few days ...

 

[blisters]

Having a mate to go through it with you is a great start. You have a multimeter so pretty well you are set to tackle nearly everything on your vehicle just learn the multimeter and you'll be fine.

The thing with electronics is you have to protect the crcuit with the correct fuse or circuit breaker. If you make that your number one rule then you have little to worry about. The test I use is what would happen if I pulled a wire out and touched ground and the answer should be no damage except for a blown fuse. I also solder and heatshrink terminal joints for robustness.

The fuse block I linked to as an example has leds and I wouldn't buy that for a 4wd as it adds complexity sorry bad example. Find one that is solid with plenty of meat around the bolt holes.

To wire it in if you look at the jaycar fuse block it has 100 amp input and ten 30 amp outlets. What this means is you can supply a max average of 10 amps to each outlet before the input reaches its rating. But if you had three thirty amp accessories running at the same time it woud be fine totalling ninety amps but that is how you'd determine sizing for your block.

To wire it in all your accessories will be protected by the fuses in the block, but you have a 100 amp wire to the block and imagine if that fell off and touched ground. so you should fuse that as well. I would put an auto resetting breaker close to the battery so if the battery to breaker wire broke off then it would be too short to touch ground.

Protect your wiring runs with conduit and grommet holes.

Jon

 

[AngerManagement]

As an Electronics Tec; I hate most Auto wiring jobs.

So many new cars have all sorts of monitoring and computer controlled stuff and self checking = A right pain and can you do some damage, if you get it wrong

1: Get a separate dedicated fuse block as stated above...

2: Use the correct gauge or heaver gauge wiring. A long run of the wrong gauge, can cause all sorts of problems.

3: Get a separate dedicated fuse block as stated above...

4: If your not Electronics - Get a mate who is. Don't learn the hard way, on the job and burn something out.

5: Use and run a good earth

6: Get a separate dedicated fuse block as stated above... 8)

PS. Many good reasons and first hand experience as to "Get a separate dedicated fuse block "

 

[nucopia]

Hahaha I get it ...get a dedicated fuse block
I recon the $38 spent on a bottle of Bourbon is also good investment in my auto electrical education..
i bought 2 roles of 25amp wire red & black would that be ok ?

 

[blisters]

For a uhf 25 amp should be plenty but the original wiring size to the radio should act as a guide. Check online for the radio current draw to size the wire and fuse. Did you see an inline fuse on the wire as a lot of radios have them out of the box, it could be this fuse that is blown so no power is getting to the radio.
Jon

 

[baw1983]

Hi mate im a diesel mechanic I work on anything with an engine basically the best advice I can give you is pull out anything aftermarket that isnt in use and start again at least then you'll know the system, makes tracking future problems a lot easier and whatever you wire in you know is done right

 

[silver]

Dont offer the boubon up front (being drunk doesn't make electrical work any easier) ,... just put the offer out there that you have a bottle of bourbon to share with whoever can fix your electrical problems properly !

 

[nucopia]

For a uhf 25 amp should be plenty but the original wiring size to the radio should act as a guide. Check online for the radio current draw to size the wire and fuse. Did you see an inline fuse on the wire as a lot of radios have them out of the box, it could be this fuse that is blown so no power is getting to the radio.
Jon

Yep the UHF has two wires coming from the back of the unit, one black one red , the red has an inline 2 amp fuse( not blown) one is a male the other has a female connector.
I have already removed the UHF from the car to test it and it works fine.
I was planning to remove dash board panels to day to access the wiring to trace the UHF radio wires back and see why no power is getting to the radio. i was also planning to remove anything that was not in use.
Have to put every thing on hold for today , as we have heavy rain showers and I dont have any where under cover to work on the car.

 

[DrDuck]

All good advice above.

If you just want to get the CB going, wire it direct to the battery and place a fuse in each lead, close to the battery. Make sure the hole in the firewall is grommeted.

You will have to remember to turn off the radio though!

It is slightly more complex to wire it so that it switches through the accessory circuit, best to get some advice or experienced help to do that.

 

[Jaros]

That's what i've done Dr Duck. I also have installed a multi pole +ve battery terminal to make it easier to connect extra's like this.
Jaros

 

[blisters]

I'd reconsider your wire size as 25a is bulky for the application. For hf it'd be required but wire bundles get large really quickly.
Jon

 

[nucopia]

All good advice above.

If you just want to get the CB going, wire it direct to the battery and place a fuse in each lead, close to the battery. Make sure the hole in the firewall is grommeted.

You will have to remember to turn off the radio though!

It is slightly more complex to wire it so that it switches through the accessory circuit, best to get some advice or experienced help to do that.

Cheers Doc
At the moment every thing is on hold with the rain and no undercover
I have an after market repair /workshop manual that has extensive wiring diagrams in it. Which I should probably study while its raining. Not that im going to understand much of it.
My first thought was to tap into one of the two cigarettte lighters on the dash but not aure if thats a good Idea or not.
I could maybe also run it directly off the battery through an after market switch mounted on the dash board. Ther are two such switches on the dash already just need to take off the dash panels and expose the wireing to get an understanding of what went where and what for.
Im guessing the last owner had spot lights and other things wired into the system( now removed) plus there is still the black widow alarm system to figure out. i know it has power going to it as a light on the dash flashes when I plug the wireing harness back in to the unit. The siren is located in the engine bay and the wires conecting it have been cut. Both sets of keys have sensory units on them I first thought they were for an auto garrage door opener , but i think now they have something to do with the alarm system.
Cant do much now until the rain stops and i can get in and expose the wiring behind that dash ..

 

[The Green Wanderer]

I feel your pain nucopia, as im sure does anyone whos done their own vehicle mods!

Great start with the repair manual, at least now you can get in and identify the original wires by colour (there's a colour chart on the schematics) and pull the extra wiring out.
Best to start at the battery and work back, follow any suspect wires and find where they go through the firewall to the dash loom then on to whatever was attached. Along the way you can usually see if and where the loom or the accessory it runs to has been hijacked.

Im assuming you have an older landcruiser, 60 or 80 series?
Up to you if you remove the alarm system or not. Personally im not a fan of the black widows especially the older units.
Sounds as though the unit in your truck has/had a remote locking system attached to it, unfortunately that means more wires to follow.

As for the UHF just follow the installation instructions that come with them, either wired direct to the battery with an independent ground and appropriate fuse or through the vehicle accessory wiring which is controlled by the ignition barrel.
Both have ups and downs, if you go direct then you have to be sure your radio is off when you switch the truck off. Up side is that if your stuck or lose your keys etc you can switch the radio on to get help.
The reverse is true for putting it through the accessory switch. It's really a matter of habits, if your the forgetful sort then go with accessory, if you misplace keys often then go with direct connection.

If you can conscript a mate with some electrical knowledge then thats even better, even if you have to coerce them with their poison of choice
And if you get stuck, just post some more on here and im sure the local boffins will jump in with plenty of answers and advice.

Happy hunting,
TGW.

 

[baw1983]

What model cruiser is it?

 

[nucopia]

Thanks Guys
The weather was kind this morning so was able to get out and remove the dashboard panel and access the wireing.
Found the problem was a missing fuse further up the line.
The UHF is now receiving power and seems to be functioning.
what I need now is an aerial to see if the unit will transmit and recieve.
Probably go into supercheap or one of the other stores and see whats available/compatible.
I have left much of the ancillary wireing to do with the black widow alarm in tact as it seems way more complicated for me to feel confidence in what I am doing. i did notice some wire on the wiring harness that is disconnected from the unit have been cut.
Every thing works that should now so until I gain more experience confidence or I can get the help of some one who knows what they are doing, I will just leave things as they are for now.
Its a landcruiser prade 1998 model is VZJ95R 3400v6 quad cam(5VZ-FE) petrol and LPG
Came with an ARB diff locker ,air compressor and air hose...both working thankfully.
My next project is to find a 2nd hand bull bar and attach driving lights...

 

[nucopia]

uHF radio update .. Radio has power all functions seem to work aerial is connected but no transmission of reception.
So back to the drawing board to figure out whats weong...might be better to just go oout and buy a new unit ..

 

[The Green Wanderer]

Lol even better a fellow prado owner!!
I have a green and silver 97 vx grande.
Good to hear the uhf is up and running. Is there an ariel stub mounted somewhere? Could be worth checking that the cable isnt frayed or loose.

 

[blisters]

Have you mounted your aerial or trying it unmounted? Some aerials are ground dependent and others independent but may still need to be grounded to use the vehicle body as a ground plane. If your mate has a working uhf then you could power your radio off their battery and hook up to their aerial to test.
Jon