Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: Blackie_No1 on 12 November 2011, 11:46:16

Title: Electrical gremlins!!
Post by: Blackie_No1 on 12 November 2011, 11:46:16
My omega elite f/l is starting to do my head!!

So the auto box crapped itself first!  Then, possibly coincidentally, it has developed electrical gremlins, one day whilst sitting listening to the radio, I tried to start the car and I lost the radio and the instrument panel.  After about ten minutes of panicking and pulling fuses in and out, I decided to try and start it again and everything was working.

Driving home from work last night, listening to the radio, heated rear window on, ecc on auto and obviously the headlights on, everything went dark, no lights, no radio, no instrument panel.  After blindly fumbling in the dark i discovered one of the BIG fuses had popped, the main electrical system fuse (80amp) had pretty much melted itself in oblivion!!

(http://i10.photobucket.com/albums/a101/teamlsm/d9311431.jpg)

Anyone have any ideas or suffered from a similar fate?
Title: Re: Electrical gremlins!!
Post by: freecall666 on 12 November 2011, 18:14:09
looks like a bad short some were, will need a meter to try and find that have you had dash out or anthing out electrical, or could be a short in radio?
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 12 November 2011, 20:04:05
No mate, the only two bits of work done to the car is a second hand auto box fitted(with the original cars selector switch) and a pair of new exhaust centre sections.

Possibly could be the head unit as both times the radio/instrument panel went I had a cassette in the cassette player. The first time it happened I was trying to get the CD cartridge to stay in the HU.

If I get a multimeter what should I be looking for?
Title: Re: Electrical gremlins!!
Post by: Andy H on 12 November 2011, 20:16:37
There really isn't much space for the wiring behind the head unit. I wonder if a trapped wire has made contact with some metalwork?
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 12 November 2011, 20:27:17
Well now that you say that, one of the little Allen screws that go into the front of the headunit, which is a ccr2006, is missing, so I assume it has been out. The ecc servo on the drivers side isn't working so I assume someone maybe took the HU out to get at the heater?
Title: Re: Electrical gremlins!!
Post by: freecall666 on 12 November 2011, 20:41:31
would check wiring as if its done that to fuse, may have melted a wire or 2 some were else, did you have any burning smells?in cab....
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 05:11:43
Strangely no, I thought I woul have had a burning smell in the cab as well
Title: Re: Electrical gremlins!!
Post by: freecall666 on 13 November 2011, 05:32:58
do you know what the drain on the battery is with out any thing on, then check one by one with radio etc on see if you can find a linc may cost a few fuses.. then when you find the bad unit etc check it wires to fuse etc, would find it out dont want a fire in cab.
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 07:35:20
Cheers for that, a mate is gonna throw a multimeter round to me, though when I get home from work I will remove the head unit just to have a peek and see if there is anything obvious
Title: Re: Electrical gremlins!!
Post by: Martian on 13 November 2011, 11:14:32
That looks more like heat damage to me, and that generally occurs over a period of time.

First thing I'd check is that the spade connectors in the fusebox haven't loosened up, because even the slightest hint of a loose connection at those kind of current levels will get the heat building up quite quickly.
Title: Re: Electrical gremlins!!
Post by: Dave DND on 13 November 2011, 13:03:05
Unlikely to be head unit related - they are often protected by 15 / 20A circuits and those fuses would have blown long before an 80A one did.

80A fuse is a MAJOR fault, not just a faulty head unit, module etc, this would be more like a trapped or exposed wire, and has not happened instantly, it has happened over a period of time due to the melting etc.

A fault should blow a fuse instantly, but a loose connector could also draw lots of amps, heating the fuse up like a heating element over a period of time until it melts rather than blows.

Good luck with the search.

 :-\
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 14:53:23
That just makes matters worse! Lol! I've put a new fuse in it, and based on what your saying it should have popped? To date, it isn't even showing signs of discolouration?

This fuse seems to be tied into the head unit, instrument panel, heater controls, hazard lights(as they didn't even work) interior lights and headlights, as these all failed when the fuse melted into oblivion!
Title: Re: Electrical gremlins!!
Post by: Dave DND on 13 November 2011, 15:10:52
That just makes matters worse! Lol! I've put a new fuse in it, and based on what your saying it should have popped? To date, it isn't even showing signs of discolouration?

This fuse seems to be tied into the head unit, instrument panel, heater controls, hazard lights(as they didn't even work) interior lights and headlights, as these all failed when the fuse melted into oblivion!

Then I would be measuring the current beore doing anything else, as next time could be a fire

 :-\
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 15:56:52
Where should I be measuring the current? At the fuse?
Title: Re: Electrical gremlins!!
Post by: Dave DND on 13 November 2011, 16:30:55
That would be a good place to start from

 :y
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 17:27:15
Ok, have done a bit of research through the TIS2000 software and with the Haynes manual and I have discovered that this is fuse FV6 which, has a direct feed to/from the Auto Transmission ECU.  Now, I mentioned that the auto box had been changed at the start of this thread, and that the gremlins have only started from the gearbox replacement.........

coincidence?
Title: Re: Electrical gremlins!!
Post by: Andy H on 13 November 2011, 18:31:45
Not quite sure how you will go about measuring a dc current in excess of 80 Amps :-\

My multimeter can measure up to 500mA on the normal measuring terminals then there is another 'shunt' terminal that can measure 10 Amps.

The 500mA input is protected by a fuse. The 10 Amp shunt isn't protected. I imagine that if I passed 80 Amps through it the multimeter would glow briefly before turning into a molten lump of plastic  :(
Title: Re: Electrical gremlins!!
Post by: Osprey on 13 November 2011, 18:42:23
Clamp meter probably simplest - although some cheap ones are pants on DC. 
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 18:48:29
Clamp meter probably simplest - although some cheap ones are pants on DC.

Huh??
Title: Re: Electrical gremlins!!
Post by: Andy H on 13 November 2011, 19:15:28
Clamp meter probably simplest - although some cheap ones are pants on DC.
Almost all clamp meters are only able to measure AC current.

A quick google turns up some that can measure DC but they start at £60

http://www.google.co.uk/products/catalog?q=dc+clamp+meter&hl=en&um=1&ie=UTF-8&tbm=shop&cid=2143780759977547088&sa=X&ei=qBXATqCFDYaAhQfryp3IBA&ved=0CHgQ8wIwAA

http://www.google.co.uk/products/catalog?q=dc+clamp+meter&hl=en&um=1&ie=UTF-8&tbm=shop&cid=8537691114124574307&sa=X&ei=qBXATqCFDYaAhQfryp3IBA&ved=0CHsQ8wIwAQ

http://www.google.co.uk/products/catalog?q=dc+clamp+meter&hl=en&um=1&ie=UTF-8&tbm=shop&cid=9144676638356082232&sa=X&ei=qBXATqCFDYaAhQfryp3IBA&ved=0CH0Q8wIwAg
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 13 November 2011, 19:33:27
I just did a quick voltage check, engine not running, 12.4v at battery, engine running - 14.13 at battery, at fuse 14.13, put car into gear, 14.12, put it into neutral, 14.13. . . .
Title: Re: Electrical gremlins!!
Post by: freecall666 on 13 November 2011, 21:14:47
has it been raining alot were you are?, if so get under car and check the wireing plugs, make sure the seals on all plugs are fine. check every were there is a plug bar for sensors they would come up on info display if there was a fault.
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 14 November 2011, 05:38:12
It was raining here about two weeks ago, we had bad flooding and I towed my bro in law out of a rather deep puddle lol, auto box went a few days after that, so maybe there still might be a little water somewhere??

Problem is I have a slipped disc and can't get under the car at the mo :(
Title: Re: Electrical gremlins!!
Post by: Kevin Wood on 14 November 2011, 09:44:13
It was raining here about two weeks ago, we had bad flooding and I towed my bro in law out of a rather deep puddle lol, auto box went a few days after that, so maybe there still might be a little water somewhere??

Yep. It'll be in the gearbox selector switch. A common problem when driving through floods.

Do the LEDs by the gear selector accurately follow selector position?
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 14 November 2011, 14:14:23
Funny the guy that did the gearbox said it could be that. They do seem to follow the selector accurately, but . . . . .

And this may be a big BUT. . . .

a day or two before the fuse went all the led's lit up when I was going from N to R, this has also happened a day or two before the first time I lost the radio and dash (but the fuse must have melted itself together)
Title: Re: Electrical gremlins!!
Post by: freecall666 on 14 November 2011, 18:20:20
check the seal when you can or give a small kid some pence and get them under to fix it good luck with you discs dont damage your self up to much, good luck m8 get well soon. :y
Title: Re: Electrical gremlins!!
Post by: Blackie_No1 on 14 November 2011, 18:41:37
Thanks buddy!  :y