Help! I've got an electrical prob but battery OK?!

[TUS 373]

My car had been performing superbly with its last appearance being at the BNG.

Around a week later, I needed something from out of the boot and discovered that the battey was very flat with windows being slow to operate etc. I slapped the car on to an Accumate - but even a week later the battery had not re-charged. I thought it was the battery, so replaced it with a new one this afternoon. Not only was it a brand new battery, but I put it on charge overnight so it was all ready to go.

THE PROBLEM?
The car will barely crank over at all even though the voltage is being reported OK at 12V on the dash, all lights work etc. So where is all my juice going to? Not to the starter!! In short, I know that it is not the battery, ignition coil fuse, alarm or immobilser (I can lock and unlock, prime fuel pump etc).

Can anyone help me please?

Thanks in anticipation
Bryan

[alans]

do your lights dim if you try to crank her over? if not I would suggest its either the starter motor connections or the starter motor itself.

[TUS 373]

Just tried that. Looks like all power is going to the starter when cranked. Radio goes off etc. Soon as I release the key, all power is restored. The starter struggles to turn the engine over more than twice until all power seems to have been used.

Where do I start?????

[alans]

IIRC when you turn the key to start the power to ancillaries like the radio are lost, so isn't really any indication.
I would suggest if you have an multimeter to check the voltage to the starter, and possible clean the connections to the starter and the earth.

[TUS 373]

Bonnet off time coming up then! Oh bugger...

The irony of course is that it was OK when I last put it to bed! Thanks for your suggestions.

[donaldhunter]

Sounds like a dead battery. Should indicate more than 12v when charged.

[TUS 373]

Not the battery. Brand new and fully charged. certainly not that!

[lady topaz]

Just heresay and I daresay completely wide of the mark, but when I bought my car the dealer told me to disconnect the boot interior light if not using the car for a few days as leaving it connected would drain the battery. This may be complete twaddle but all the showroom cars do have theirs disconnected. I dont pretend to understand why this should be if the light isnt even illuminated and probably has bugger all to do with your prob but who knows?

Let us know if you solve it.

[TUS 373]

Hi Diane
Strangely, my car has been wired with a little common sense by TVR - well, with respect to the boot light anyway! It only comes on when the side/headlights are on and the boot is open i.e. night time operation. I get the impression that with some cars, the boot light comes on whenever the boot is opened, regardless. It had crossed my mind that despite this, I may have inadvertently flattened the battery by not shutting the boot properly and hence a dead battery. Sadly, this was not to be the case as even with a fresh new fully charged battery - I'm having bother! Well, I suppose it was my turn eventually wasn't it?

[lady topaz]

TUS 373 said:

Hi Diane Strangely, my car has been wired with a little common sense by TVR - well, with respect to the boot light anyway! It only comes on when the side/headlights are on and the boot is open i.e. night time operation. I get the impression that with some cars, the boot light comes on whenever the boot is opened, regardless. It had crossed my mind that despite this, I may have inadvertently flattened the battery by not shutting the boot properly and hence a dead battery. Sadly, this was not to be the case as even with a fresh new fully charged battery - I'm having bother! Well, I suppose it was my turn eventually wasn't it?

Your still smiling Bryan and thats what its all about. Let me know what your prob is just in case. Always useful.
Cheers Di

[TUS 373]

Diane,
I think it may be a battery virus... that's eating my volts. Either that or a wire worm.

Ooops - bottle of red doing the talking now.

[lady topaz]

TUS 373 said:

Diane, I think it may be a battery virus... that's eating my volts. Either that or a wire worm. Ooops - bottle of red doing the talking now.

2nd bottle of white just un-corked so travelling on the same road

[TUS 373]

Wooooooooh, you're overtaking - swerve - swerve

[lady topaz]

Gotta get in the mood for my hols yippeeee

[Nick Elliott]

Sounds to me like Tuscan dodgey earth strap syndrome.There is an earth strap somewhere between the starter motor and chassis and on some of the earlier cars this use to break up causing the symptoms you describe.

Nick

[T88CAN]

Hi Bryan bl###y TVR`s my 2penny worth is, Even though you have a new battery still try jump starting with a slave battery or donor vechicle, i take it you`ve got the special leads? if that doesn`t work i second alans and would go for the starter motor i`m not sure were this earth strap is on the tuscan? put a call out to andyvdg or graham66 they seem to be knowledgable good luck Tony


>> Edited by T88CAN on Saturday 20th September 21:56

[TUS 373]

Thanks guys,
Earth strap is a possibility. The thing with Tuscans is......because the bonnet is bolted down, you don't develop the same sense of what goes on under there compared to the other TVRs. And, its not such a quick thing to check this and that. Anyway, when I can persuade my wife to move her car out of the garage and give me a lift off with the bonnet, I'll be checking the earth strap.

Tony, gave it a go with the two batteries and Leven leads - no difference. Infact, as it was the new battery I was trying to jump start with, I thought I may have had a dodgy connection with the leads instead (!) - hence that is why I went ahead and swapped the batteries over putting the new one in.

So, looks like I may not have needed to spend £70 on a new battery now. On the upside though, it was probably the original battery of 3 years vintage that I was replacing - so not a bad idea to get it swapped over for piece of mind anyway. Better now than having a dead battery when away from base. I also have a spare one now for jump starting with!

Tony, how are things shaping up with your Tuscan - any news?
TTFN

Bryan

[T88CAN]

Bryan, things shaping up nicly at the factory and have agreed not to say too much will call you soon
Tony

[TUS 373]

Sounds good Tony. I'm sorting mine out at the moment. Found one end of a big earth strap attached to chassis and just cleaned it up and rebolted it. Can't see the other end at the moment - but assume it goes to the rather inaccessible starter motor. I'm going to try it now and if it does not work, I'll have to take the front wheel off for a better look. Ah the joys.......

[TUS 373]

Update time.

I stripped out the airbox to find the starter motor and everything looked OK - nothing obviously wrong. Time to call out the RAC who after 2.5 hrs said they were stumped. They could jump start the car with 2 fresh power packs together - but not with one. They could also jump start directly to the starter motor which after a little struggle, started the car.

There can only be 4 elements to this problem: battery (brand new and freshly charged), the wiring (which with an added battery pack started the car), the startet motor (well, it can start the car), the engine (we got it started, so its not seized or anything like that). Everything individually checked out OK but put them together and we still have a non-starter.

As far as earths are concerned - there is no earth strap from starter to anywhere - it earths through contact with the engine, which in turn is earted to the chassis - so that appears all OK.

My thoughts are turning towards the starter motor. Is it conceivable that it has failed someway internally so it takes more current than normal to get it to operate. It is drawing 300A the RAC man said - maybe a little on the high side.

So for now I am quite , and so are the RAC, who credit to them, did their very best but could not come up with a diagnosis.