Omega Owners Forum

Chat Area => General Discussion Area => Topic started by: nuclear onion on 09 October 2007, 19:29:17

Title: Auto Electrician
Post by: nuclear onion on 09 October 2007, 19:29:17
Is anyone here experienced in auto electrics and willing to try to diagnose a weird fault on my friend's Astra. He's tearing his hair out (and believe me, he can't spare any) so I said I would ask on here for him

Thanks :)
Title: Re: Auto Electrician
Post by: Kevin Wood on 09 October 2007, 19:36:58
Well, give us the details and I'm sure we can give him some suggestions. Whereabouts is he located?

Kevin
Title: Re: Auto Electrician
Post by: nuclear onion on 09 October 2007, 19:41:58
Ok he lives in Chesterfield, same as me.

As far as the fault goes: When the ignition is on, the dashboard is completely dead, all the lights are out, including oil and battery, plus the temp and fuel gauges are also not working.

Start the engine and sometimes the rev counter comes on, sometimes it doesn't. If the rev counter fails to work, so does the speedo. The battery light comes on above 1000 revs and then stays on but the engine itself is running fine and the battery seems to be holding a full charge. None of the other engine related lights come on.

Also, it seems that the when the handbrake is released, the lights behind the centre console radio/clock display go out. Put the brake back on and the console lights up again.

I wondered if it could be the voltage regulater thingy in the instrument panel so we changed the clocks but it made no difference
Title: Re: Auto Electrician
Post by: Kevin Wood on 09 October 2007, 19:52:04
Sounds to me like the supply to the dashboard is not there. The reason I say that is that the alternator light is doing the reverse of the expected behaviour. Normally it has 12 volts on the supply side and the alternator grounds it before the engine starts. Once the alternator is charging there should be 12 volts at the alternator side of the light and 12 volts at the supply side meaning it goes out. In this case it obviously doesn't have 12 volts at the supply side. The current feeding through the alternator light could be enough to power the instruments erratically.

I would check the fuse(s) that power the instrument panel as a first step.

Cheers,

Kevin
Title: Re: Auto Electrician
Post by: nuclear onion on 09 October 2007, 20:01:13
Thanks Kevin, will check that out in the morning and report back :y
Title: Re: Auto Electrician
Post by: Andy B on 09 October 2007, 20:10:59
Which Astra? Mine & SWMBO's Astra G's clocks are locked in by a pivoted hook arrangement. It's easy to get it wrong when you put the clocks back in the dash.
Title: Re: Auto Electrician
Post by: Entwood on 09 October 2007, 20:12:53
If everything is dead, and the odd "extra" is intermittent ... I wonder if you have an earthing problem ?? I'd check for a common earth lead that has broken/come loose
Title: Re: Auto Electrician
Post by: TheBoy on 09 October 2007, 20:32:13
Worth checking the earths as well.
Title: Re: Auto Electrician
Post by: davlad22 on 09 October 2007, 21:15:08
^^^^^
Aye

Yes, which shape astra? MK2, MK3(F) MK4(G)? How did the problem arise? After doing some work? Changing a component? After switching on one morning? Witchcraft?  :-?
Title: Re: Auto Electrician
Post by: nuclear onion on 09 October 2007, 22:08:01
its a Mk3 and as far as I know the last work that was done on it before it started acting up was to have the towbar and electrics removed.  After that it blew two fuses (he didn't say which ones). He then changed them and its since then that he's had this problem.
Title: Re: Auto Electrician
Post by: holey head on 10 October 2007, 18:29:25
check where the wiring has been romoved for towbar. check nothing is shorting thats what it sounds like to me. then check the fuses. no point changing them first for them just to blow straight away again!
Title: Re: Auto Electrician
Post by: smoothomega on 10 October 2007, 21:02:08
Did it have twin electrics on the tow bar? Just wonder if the charging side of things has been disconnected fron the alternator/relay. if not and the old cable is going to earth this will have all sorts of strange effects least of all a potential fire hazard, disconnect the battery and sort it sooner rather than later would be my advice, for what its worth
Title: Re: Auto Electrician
Post by: Kevin Wood on 10 October 2007, 22:33:25
It doesn seem to point to a shoddy job of removing the towbar electrics  :-/

Kevin