Alternator dead?

Alanstrainor

So, after washing the car today, I went around to the garage to check tyre pressures. After testing pressures, I got in and tried to start it, and it hesitated and stopped. Tried again and it fired right up. I knew something was wrong though!

So I get home, and turn off the ignition, and try start it again and nothing. All lights etc turn on no problem. All I get when I try and turn it over is a loud CLICK. And nothing. I connected up my battery to my dads 5 series to make sure it wasn't a battery issue and it made no difference. Just a click.

So, now I'm wondering how to better diagnose this, I'm thinking its the starter motor, but it's just a guess on my part. Anyone have any ideas?

N.B
It should be noted that I changed my plugs yesterday, and had no issues. Covered 100 miles or so, and started stopped without any bother. But it is very coincidental for this to happen almost immediately after...

Alanstrainor

Update.

Went out to the car an hour or 2 later and it started right up. I was baffled. Took it for a spin, and then 5 minutes into the spin I noticed the battery light turn on. I high tailed it home, or at least tried to. Started to lose electrics, wipers, lights etc. Turned everything off to try and nurse it home. Managed to get it off the road and parked in an estate.

So now I'm thinking alternator...I do know that my alternator was reconditioned before I bought it two years ago.

Interslice

Alanstrainor wrote: »

I connected up my battery to my dads 5 series to make sure it wasn't a battery issue and it made no difference. Just a click.

If your battery was completely dead you might have to let the other car charge it for a bit and even still it might not work. Not enough power in 5 series alternator to charge your battery, it's own battery and power your starter. Try swapping the batteries instead

Alanstrainor wrote: »

Update.

Went out to the car an hour or 2 later and it started right up. I was baffled. Took it for a spin, and then 5 minutes into the spin I noticed the battery light turn on. I high tailed it home, or at least tried to. Started to lose electrics, wipers, lights etc. Turned everything off to try and nurse it home. Managed to get it off the road and parked in an estate.

So now I'm thinking alternator...I do know that my alternator was reconditioned before I bought it two years ago.

Sound like your alternator alright. Could be just the regulator. You can do nearly all the test with just a multimeter and a running engine:o.

http://www.pelicanparts.com/BMW/techarticles/101-Projects-89-Alternator/101-Projects-89-Alternator.htm

BillJ

I had some similar symptoms with my e46 (318) and it was the crankshaft position sensor. Not the exact same symptoms but worth looking into.

For months I had an issue where my battery light would flick on and the revs would drop. Then one day I was driving along and battery light came on, lost all electrics and had to pull into the side of the road. Tried turning it on, only got a clicking noise, no cranking.

Got towed home. Car started fine itself then about 2 hours later.

Have you got an obd scanner? mine was throwing a fault for crankshaft and camshaft sensor but the camshaft sensor occurs due to mis-communication with the crankshaft sensor.

Alanstrainor

I do have a scanner. A Bluetooth jobby from eBay. going to read codes when I'm home!

Alanstrainor

Think I have my issue sorted.

Positive battery cable was loose in the engine bay, took it off, gritted it down as there was some minimal corrosion on it and then screwed it back on properly. Ran the car for 20 minutes and saw no ill effects. Fingers crossed that's it sorted. The car wasn't showing any error codes either which is good! Cheers for the input gents!