full beam or ignition switch to 'start' kill electrics tempo

[menostig]

rarily.

Yes. Car has been working fine for ages. Then I do some things... and now it doesn't.

1- turn key to first position and everything works (e.g. guages, a/c fan, horn, fuel pumps, hazards, wiper, sidelights) with 12v shown on voltmeter
2- turn key to next (final) sprung indent and everything continues to work
3- hold key there and press start button and everything stops working (gauges, fan, horn, pumps, hazards, wiper, sidelights) whilest a relay clicks frantically five times
4- remove ignition key

Try again and I can repeat 1 and 2 i.e. everything works again then it stops working at 3.

Alternatively:
1- turn key to first position and everything works
2- try all switches (except ignition or full beam flash or full beam) and everything works as it should
3- go from sidelights to full-beam on either the flash button or foot switch and everything stops working (gauges, fan, horn, pumps, etc)
4- switch everything off
5- turn key to first position and everything works once more

Why does ignition 'start' or full beam temporarily remove any power ?

The only thing that I think i've done of relevence is replace the rear number plate light (which works at 2 on sidelights) and its local wiring.

Since first posting as 'starting gremlin' I've also charged the battery, checked all fuses and replaced the ignition switch... to no avail.

please help ?
cheers
Roger.

[cortina1]

sounds like either the battery is not holding charge or earthing on battery could be loose. The starter and main beam will be the two items that require the greatest power and hense will show any system defects. Once you have checked battery connections could just put on another battery on jump leads to see if any difference given?.....or it could be more complex?

[steve_d]

Have to agree with Mark.
Everything is being pulled down by heavy drain from headlights or start.
I would start with jump leads to another battery if that makes no difference then go looking for;
1. A bad earth. This will be battery to chassis or engine to chassis i.e. a large connection.
2. A poor connection on a major live side.

I favour dead battery.

Steve

[menostig]

Ok so added the impreza's battery to the equation and now reading another volt on the Ultima's Voltmeter so all jumpleads wired correctly. And again get the same sequence:

1- turn key to first position and everything works
2- try all switches (except engine start or dipped beam flash or full beam) and everything works as it should
3- go from sidelights to dipped headlights on lightswitch, or try full beam on the flash button, or try ignition start and everything stops working (sidelights, gauges, a/c fan, horn, fuel pumps, etc)
4- switch everything off
5- turn key to first position and everything works once more

Why does ignition 'start' or dipped beam or full beam temporarily remove any power ?
And why does pressing the full beam flash button result in a high pitched squeek noise from the relay's location ?

I have now removed the ignition key switch, battery, battery earths and engine/gbox earths from the equation.

cheers
Roger.

[menostig]

Hmm, turned out to be a simple thing, I cleaned and redid the battery terminals properly, now all works.

[stig]

menostig said:

Hmm, turned out to be a simple thing, I cleaned and redid the battery terminals properly, now all works.

Don't you just love fixing electrical problems

That's one reason I crimped/soldered/re-crimped and insulated every connection I made - and there were alot of them!

[GTROne]

Hmmm..exactly the same thing happened to me on a petrol fourcourt once. After a 2 hour wait the, RAC man came along and cleaned/tightened the battery terminals and all was good. I felt a real idiot though !

[cortina1]

nice to have a happy ending, glad you found out the problem, bit of torture but just think of all the experience gained. Mark