Car wouldnt start this morning

[r055]

when turning the key the starter motor turns twice (slowly) then the dash cluster light flashes like mad... stops... then turns over twice again...

starter motor gubbed?

[tut]

Try starting it in first gear so that it jumps forward slightly.

tut

[r055]

thanks Tut - i'll try that later when i get home...

[robin]

thanks Tut - i'll try that later when i get home...

No, don't do that. The fact that the starter is turning the engine over means that it isn't a problem with the starter motor.

Your battery is flat (OR you have such a bad earth path that the battery appears flat).

Cheers,
Robin

[tut]

Robin

I have an occasional problem that we have never been able to trace. Never happens from cold, but sometimes after re-fuelling or start up from the pit lane.

The starter actually starts turning, then gives up. If I try again in gear, then clutch in, it is fine.

tut

[Corranga]

I had this a few weeks ago. My car had been sitting, I tried to start it, assumed the battery was dead as it turned over a couple of times, didn't fire into life, the dash died, then the car beeped. I returned to the car a couple of hours later and all was fine!

[Rich H]

Was it particually cold? Batteries don't like getting cold their capacity drops, I assume that it mus thave warmed up a bit and the battery recovered a little.

My Elise battery is flat, and does not last long when fully charged either, time for a new one I suppose.

[robin]

The dash goes clickety click because the voltage regulator is dropping out and the supply voltage to the digital electronics on the dash (and the relays that control the lights) is dropping below the power on reset level, so the dash resets and the stepper motors and relays click in and out as the voltage goes up and down (cranking creates a sinusoidal voltage - at TDC the starter is under maximum load/slowest spin speed, so consumes more current than at 90 degrees after TDC - hence the repeated clickety click).

If this happens while you are cranking there are only two possible causes:

(1) The battery is not very well charged, and the cranking effort is causing it to drop it's supply voltage to less than the regulation limit of the dash.
(2) The battery is charged, but there is a bad earth between the battery and the chassis - when you pass the 100A or so that the starter needs through that bad connection, it causes a voltage drop across the connection (ohms law, V=IR, if I=100 and R=0.1ohm then V is still 10V - you only have 12V to start with!!). The dash sees this as a drop in supply voltage (though actually it is a rise in the earth potential, but who cares) and drops out.

There are other problems that can occur with the starter motor and gear itself, but these will not have the clickety click symptom associated with them. Starting in gear is a bad idea.

Cheers,
Robin

[Pedro]

Agree with Robin, Try a new battery, it's easy to swap out, and they don't cost that much...You might want to turn your alarm off first though with the key. Then turn it back on after swapping the battery with the key again, then you may have to reset it with the fob.

Cheers,
Pete

[r055]

bought new battery and cleaned up connections...

all ok now - thanks again Robin & Pete!

now the panic is over at getting the car to Ali's for tomorrow!