No 12v electrics

[nin73]

Hello,

Have come back to my van after the winter lay off to find out that the 12v lights, water pump,etc are not working. Checked the Zig CF8 unit to find that the middle 10amp fuse had blown. Replaced the fuse and turned on the 12v power, green light so all good. Tried the lights, fuse blown straight away. Nothing else works.

Didn't have any more fuses so whilst i was waiting to go get some thought i would put the battery's on charge. Took over 6 hours for the battery charger to say that they were fully charged. I have the main battery and leisure battery linked so when i charge the main it charges the leisure. Zig unit never showed a red light at any time.

Once it was all charged tried a new fuse blew again straight away. Could my battery be the cause to this. Any thoughts?

[ghost123uk]

Not the battery, if the fuse blows when you operate the light switch then you have a short circuit somewhere in the lights wiring. You will just have to find out where it is and fix that. Are they florescent lights? If "Yes" then the little circuit in the actual light could have gone faulty. Try disconnecting the wires inside the light(s), make sure they are not touching anything, maybe put a bit of tape on them temporarily, then operate the switch. If the fuse does not blow then, it must be a faulty unit in the light. If it turns out to be the case, this would be a good time to change the innerds to more modern LED strips = less power consumption.

Aside = Nothing to do with your problem, but have you been occasionally charging both batteries during this long lay up ? If "No" then you are very lucky they are not cream crackered.

[nin73]

Hello,

Unfortunately i hadn't been charging both battery over the lay off. Stupid i know!

I put them on charge and took the van out for its mot, Fuel pumps failed at the MOT so this was replaced. Took her for a 2 hour drive, ran lovely, then pitched up and noticed that the lights and water pumps were not working. I did get the spark to the fridge going though so had nice cold beer.

Would nothing else work if only one fuse has blown in the Zig unit?

[1664]

Would nothing else work if only one fuse has blown in the Zig unit?

Wholly depends on how your van has been wired and connected to the Zig. The idea of seperate fuses is to spread circuits about a bit so if a fuse ruptures you don't lose everything because of a fault on one piece of equipment or one circuit.

I know it's a high top but what conversion is it?

[nin73]

Would nothing else work if only one fuse has blown in the Zig unit?

Wholly depends on how your van has been wired and connected to the Zig. The idea of seperate fuses is to spread circuits about a bit so if a fuse ruptures you don't lose everything because of a fault on one piece of equipment or one circuit.

I know it's a high top but what conversion is it?

Hello, Its a Komet conversion.

When i have had fuses blow before i am pretty sure other things worked. This time nothing is working apart from the spark for the fridge, would this be off the Zig?

[ghost123uk]

The thing with this is that on a 25 year old VW camper van, over the years anything, good or daft, could have been done to the wiring. You need to establish what devices, lights, water pump, sockets, heater (if fitted) etc are being fed from where and via what fuse(s) then label them, or write it in the back of your Haynes.

A bit of advice = get yourself a cheap multimeter (~£10 from Maplins etc) and then get a friend (who knows) to teach you how to use it and a bit about 12 volt electrics. It's pretty basic and I for instance (and many others on here of course) could teach you most of it in less than an hour. It would save a lot of head scratching and stress in the future

[Fudgy666]

Not the battery, if the fuse blows when you operate the light switch then you have a short circuit somewhere in the lights wiring. You will just have to find out where it is and fix that. Are they florescent lights? If "Yes" then the little circuit in the actual light could have gone faulty. Try disconnecting the wires inside the light(s), make sure they are not touching anything, maybe put a bit of tape on them temporarily, then operate the switch. If the fuse does not blow then, it must be a faulty unit in the light. If it turns out to be the case, this would be a good time to change the innerds to more modern LED strips = less power consumption.

Totally agree with Ghost. If the action of switching on the lights is blowing the fuse then the lights have a fault that is causing them to draw more than 10 amps. As already pointed out this sounds like a short circuit somewhere.

The short has to be after the light switch, because if the short circuit was before the switch the fuse would blow straight away regardless of the switch position.

Not too sure why the other 12v supplies are being knocked out too ? Most Zig set ups have the lights on their own 12v circuit.

When it's all up and working it might be a good idea to ident the 12v outputs of the zig by switching everything on and taking each of the fuses out in turn. Off of the top of my head a typical set up will have the lights on one 12V output, the water pump on another 12v output, and 12V sockets on another. The fridge (if it runs on 12V) will normally take a 12v feed straight from the van battery via a relay switched off the ignition, this should be fused locally.

[nin73]

Not the battery, if the fuse blows when you operate the light switch then you have a short circuit somewhere in the lights wiring. You will just have to find out where it is and fix that. Are they florescent lights? If "Yes" then the little circuit in the actual light could have gone faulty. Try disconnecting the wires inside the light(s), make sure they are not touching anything, maybe put a bit of tape on them temporarily, then operate the switch. If the fuse does not blow then, it must be a faulty unit in the light. If it turns out to be the case, this would be a good time to change the innerds to more modern LED strips = less power consumption.

Totally agree with Ghost. If the action of switching on the lights is blowing the fuse then the lights have a fault that is causing them to draw more than 10 amps. As already pointed out this sounds like a short circuit somewhere.

The short has to be after the light switch, because if the short circuit was before the switch the fuse would blow straight away regardless of the switch position.

Not too sure why the other 12v supplies are being knocked out too ? Most Zig set ups have the lights on their own 12v circuit.

When it's all up and working it might be a good idea to ident the 12v outputs of the zig by switching everything on and taking each of the fuses out in turn. Off of the top of my head a typical set up will have the lights on one 12V output, the water pump on another 12v output, and 12V sockets on another. The fridge (if it runs on 12V) will normally take a 12v feed straight from the van battery via a relay switched off the ignition, this should be fused locally.

I will check that the fuse is not blowing before i flick the switch as i hadnt checked that. Only so many fuses! Thanks for the heads up

[Fudgy666]

No worries. If it turns out that the fuse blows straight away, it will make finding the short circuit slightly harder as your search won't be confined to a single lighting unit.

Again as ghost said, beg/borrow/steal a multimeter and the job is a fairly basic one using a multimeter fuction called a Continuity test.

Here is a pretty good instructional that I found using Google.

http://startingelectronics.com/beginner ... er/part-3/

A very basic summary is.

1.)Set up the meter to do a continuity test (you know it's in the right mode if you touch the 2 probes together and a crappy buzzer goes off !)

2.)Earth the black probe on a negative terminal on the back of the zig, or any exposed metal parts of the van that are earthed to the chassis.

3.)Use the red probe to test each of the 12v wires that feed your appliances. If the buzzer goes off there is a short circuit, and this is where your fault lies.

4.)Just be aware that the test has to be done on wires AFTER the fuse, as measuring across a blown fuse will always show as open circuit. Same thoery applies to measuring across switches that are already 'off'.

There is a little more to it than that, but it makes a good starting point to have a dig around for a basic fault, and using a useful setting on a multimeter.

The same function can be used to test fuses. Hold a probe to each end of the fuse. If it buzzes the fuse is good, no buzzer and there is a good chance the fuse is dead.

Hopefully this is helpful and I'm not teaching you to suck eggs

[ghost123uk]

2.)Earth the black probe on a negative terminal on the back of the zig, or any exposed metal parts of the van that are earthed to the chassis.

3.)Use the red probe to test each of the 12v wires that feed your appliances. If the buzzer goes off there is a short circuit, and this is where your fault lies.

But disconnect the +ve off both batteries before you start. If you don't and you touch a live (only 12 volt of course = you cannot get a shock) wire then some multimeters, when set on "continuity" don't like it and tend to produce a little puff of smoke

[nin73]

Hello,

Just got back and done some checks.

1. fuses do not blow when 12v switched on.
2. Tried all the lights, none working. No fuses blowing
3. Tried the water tank level button, this worked and showed the light and level. No fuse blowing.
4. Tried the floor pump for the water tank to the sink. Funny click noise from the front of the van. Checked the middle fuse and it had blown.

Any ideas what the clicking is at the front of the van? Tried looking, just some cables, nothing bare wired.

[ianboydsnr]

Get one of these, very easy to test circuits with

http://www.ebay.co.uk/itm/Sealey-PP1-Au ... 1c4172315b" onclick="window.open(this.href);return false;

Leave the fuse out, connect the probe to the battery, then probe onto the live terminal of each bit of equipment in the circuit, press button and the equipment will either work, or the led will light green negative or red positive, it will pay for itself as you won't be blowing the fuse every test!


Everyone should have one, it gets used far more than a multimeter does!

[Fudgy666]

Hello,

Just got back and done some checks.

1. fuses do not blow when 12v switched on.
2. Tried all the lights, none working. No fuses blowing
3. Tried the water tank level button, this worked and showed the light and level. No fuse blowing.
4. Tried the floor pump for the water tank to the sink. Funny click noise from the front of the van. Checked the middle fuse and it had blown.

Any ideas what the clicking is at the front of the van? Tried looking, just some cables, nothing bare wired.

1.) Do you mean that the fuses have now stopped blowing ?

2.) If the fuse is fine, but the lights still don't work, you will need to check that there is 12v on the output of the zig that supplies the lighting circuit. If NONE of the lights work, I'd guess that the problem is at the zig end. Are the lamps earthed to the Zig, or locally to the van chassis ?

3.) Sorry I don't have a water tank level button, so I'm not too sure how these are wired/work.

4.) Again slightly different from the pump on mine . . . . but, If it is just a single click when you use the footpump it could be a relay closing ? The foot switch could provide the trigger voltage to close a relay, allowing a higher current supply to be used for the pump. The pump won't work if the fuse on the supply has blown, but the relay trigger from the switch would still be ok and you would be able to hear this closing. Does the Zig provide the voltage supply for the pump ?

Kinda sounds a little more complicated than a short circuit I'm afraid. Might be time to make friends with an electrician

[nin73]

Hello,

Took the camper down to Dorchester Car Radio. They took the zig unit out to find a faulty bit of soldering, re-soldered and everything is all ok again!

All in time for Glastonbury.

[Fudgy666]

Good stuff.

Enjoy Glasto, I'll cross my fingers for good weather for ya !