No, really - you are kidding me...

[speedyveg]

Hi all,

This weekend whilst working on the 89' S2, an unusual problem occurred.

My electrics died, and I mean properly died. No clock, nothing. Absolutely zippo. I had the car started a number of times during the morning, moving it about on the driveway etc. Tested all lights, horn and washers. Later on in the morning I had to put the car on ramps, did this and switched it off. I has forgotten to put up the drivers window. Switched the ignition on and nothing happened. No electrics.

I have had time to check very little:
The terminals and clamps around the battery are good, and so is the earth strap to body.
I have some weird current draw somewhere as when you put a multi-meter across the battery you get 12v instantly. When you put it across any other part on the car (going directly from the earth) you get a range of 2 - 10 volts.
I then removed all the fuses except the clock. No clock, odd 10 volt measurement still
I then removed the clock fuse - still no joy.
I then tested across the negative of the battery and the end of the main lead going to the starter motor - you get 10 volts. It you detach the main lead from the starter motor you get an instant 12 volts - good.

I then ran out of time and will pick this up this coming weekend.
My first suspicion is the starter motor, I will bypass this to rule it out.
My second suspicion is could it be the inertia switch? Do these cars even have one?
I will also purchase a 10amp ammeter during the week so I can see how much current is leaking. I also have a variable power supply with voltage and current limiter which can be set.

My main question is :- Has this happened to anyone else?

Any ideas. I'm pretty annoyed

Thanks
Jev

 

[924nutter]

To rule the cooling fans out pull the big relay at the back of the fuse box. This is the cooling fan realy. If the temp switch has gone u/s as mine did then the fans can stick on and will drian the battery because they are not wired through the ignition. After that it is a process of illimination.

 

[Mike_Pollock]

Good call, John

 

[speedyveg]

Thanks Chaps,

I'll try this, one piece of info which I did miss out. My temperature gauge appears to have given up the ghost over winter.

Coincidence?

Thanks,
Jevon

 

[GlennS]

I like these.

http://www.tooled-up.com/product/draper-expert-12-48v-5mm-maxi-blade-automotive-tester/143572/

Plug in turn into each fuse socket and it shows you which one is pulling current and how much. Then you know which circuit is causing all the fun.

 

[speedyveg]

Thanks Glenn,

Why don't I own one of these - looks damn useful!

Thanks,
Jevon

 

[Dockrell]

Jevon,
Could your problem be the ignition switch itself.
In the dim and distant past with a Lada Niva I had complete electrical failure on the M40 in winter in the dark.
The problem was the ignition switch. The switch had a housing in two pieces with two split rings holding the two parts together. When the splits in the securing rings lined up with the joins in the housing all power was lost. Moving the split rings round solved the problem.

Hope your problem is as simple as this.

Mike
white 2.7 automatic

 

[speedyveg]

Hi Mike,

Yes - it could be as simple as this, I'll add it to the list. My running order on Saturday will be:-

Eliminate starter motor
Eliminate fan relay
Check current across fuses
Open up steering column and check the ignition switch.

There is an argument to say it is most likely the ignition switch. Let us not forget the car was running and I switched it off. Then tried to switch it on again straight away to put the window up - and it was dead. I might move your suggestion to the top of the list!

Thanks,
Jevon