Nucence MQ electrics Cutting off again

[Screwy]

Rightio, heres the scoop.

My MQ 24 Volt deisel is being a pain.
A while ago i put a message up saying the stereo was cutting out, i thought it was overheating, wrong.
I have recently noticed that my Vents Fan isnt working either, it seems to be that when the fan is working the stereo doesnt. but when u disconnect the fan or the fan stops, the stereo only sometimes comes on, if that makes sence.....
My reverse light is on my accessories also and when i turn that on my stereo instantly cuts off. Ive come to the conclusion that too much could be running off accessories?

Ive got my UHF, AM, Reverse light, 2 sets ( 4 lights ) of spotties on relays and switched, my amplifier for more speakers, my stereo unit, a little electric fan and a coupla other small bits all on accesories......

Therefore i figure ive got too much there, but wat i dont get is y the problem is mainly to do with my Vent fan. It only works when on accesries, but i always though it was 24 Volt, which makes no sence....

Please Help.

Cheers,

Screwy

[totto]

I would first look to the stereos ground connection. And then to the other item's ground connection including any power transformer (24 to 12 volt). What you describe could well be the gremlins of ground connection failure. Let's say that the stereos ground connection is wired to a power feed to the fan betweeen the switch and the fan. If your fan is not running, the stereo could be grounded through the fan motor. When you turn the fan on, the stereos ground connection then is fed with 24 volts supply, hence no real ground connection.
Sound confusing? It can be. A good rule is to let every extra item you put in have it's own ground connectin, then you are sure it's a sound connection.
Ground failure can be a pain. I once had the headlights come on in a car when attempting to crank the starter, and the car didn't even have daytime running light! When pulling the car to a start everything worked fine. Turned out the ground failure in the battery to ground cable. Such failures can cause the strangest symptoms.
Good luck

[V8Patrol]

sounds like an earth problem..... looks like you'll need to check all earth points in the cab and it may well pay to do likewise under the bonnet.

Kingy

[Screwy]

There is also another thing, when the stereo is working, depending on the conditions, and the mood its in...... it will cut out depending on volume, the louder the more frequent etc.

The other question i have is, MQ desiels have one 12 volt accesorries wire running under the dash just above the steering columb. I think this cable is drawn from both batteries as its a factory 12 volt cable and there fore would have to have a step down somewhere in there.......

Could all the stuff i have on the acc. be too much?

Screwy

[totto]

I've seen one some wiring diagrams 12-volt supply run from battery no.1 through a accessory relay to the cig.lighter.
Bad idea according to my limited knowledge of batteries and charging. Using such a solution for 12 volt supply would drain one battery of power and the charging system will never get it all the way up again to full charge. I had my stereo running from only one battery, had to charge that battery every 14. day to keep the car running.
If there's a factory converter supplying 12 volt it will most certainly have limited capasity.
Most normal converters for running stereos deliver 4 to 6 amps at 12 volt.
If you have all your accessories on the list in the previous post running off this converter, you most likely exceed the limit of the converter every now and then.
This can cause your stereo to cut off, or simply cause a thermo circuit in the converter to switch off due to exceeded power consumption.
You really should measure how many amps every accessory item draws, then add them up and see what your converter needs to supply.
Then get a suitable converter and set up a little sub-net for 12-volt use with fuses for each item.

[carts]

It does sound like a crook ground in the car. I am not sure where that 12volt accessory wire is fed from. I dont think there is a power inverter in the car from factory, so i guess that must mean that it is fed from the second series battery to provide the 12 volt. I could be wrong though.

I agree with totto, running accessories and a lot of them at that, off 1 battery is bad for the charging system. From what I understand it puts an unbalanced charging load on the system which can cause one battery to overcharge and one to undercharge, which will destroy one battery a lot quicker than the other, not to mention it wont charge properly. I also believe it shortens the life span of the 24volt reg as well.

The best advice i can give is buy a good power inverter to run your 12 volt stereo,uhf, amp etc and put 24volt globes in all your spotties and connect them across the full 24volt system. You can make your own inverters if you so desire and design them to your load requirements. Dick Smith can help you with schematics and parts.

[Screwy]

That would explain y one of my batteries died not too long ago and the other one was always fine. Ill definatly re wire some of the stuff down there in the next coupla days, though my stereo if fully cut out at the moment, as in it doesnt work at all. Fan does though. The V8 goes in soon so i will only temporarily do the wiring as it goes to 12 volt with the V8.
Still cant figure out y everything else cept my stereo works.......

Screwy