2003 won't start

[StevieS]

Hi folks. A problem has come up with my 2003 Z4 Ragtop. My ignition key locks/unlocks the car, I turn the ignition and all the dashboard lights come on as normal, when I turn the key to start, you can hear stuff "initialising," but there is nothing not even a click. It will bump start from cold within about 6 feet on a gentle slope, even in these really cold conditions. I took it for a 50 mile run and it started ok, immediately after I parked up. 1 hour later, it won't start again. Headlamps etc. are strong even without engine running. Immobiliser problem?
Sorry if this has been answered before, but I've trawled through and couldn't find anything.

Stevie

[Huz-Z]

How old is the battery?

[StevieS]

I've no idea. Over 5 years old though.

[Huz-Z]

I’ve seen other folks post here that their car does all kinds of odd things when the battery is on its way out. That may be a potential cause.

[StevieS]

Have stuck a meter on it. From cold it reads 12.2v Car won't start. Bump started, then showing 14.4v. (14.6v when revved.) Turned off, then on, won't start. Battery is BMW 12v 70ah. 570CCA. Tell tale is black, this says the battery isn't charging. If it was yellow, it would indicate a faulty battery.
New battery then?

[Huz-Z]

Could be.

Let’s see if any of the gang here have other ideas before you spend money on a battery - just in case it’s something else.

[3798j]

Originally Posted by StevieS

Have stuck a meter on it. From cold it reads 12.2v Car won't start. Bump started, then showing 14.4v. (14.6v when revved.) Turned off, then on, won't start. Battery is BMW 12v 70ah. 570CCA. Tell tale is black, this says the battery isn't charging. If it was yellow, it would indicate a faulty battery.
New battery then?

New battery?...probably. Your 12.2v reading points to that.

If the battery is
12.5 = 85% charged
12.4 = 65%
12.3 = 50%
12.2 = 35%
12.1 = drained

Testing with a load tester (many parts stores will test batteries) will definitively determine if the battery is bad.

Load testers:

[dc_wright]

Have someone try to start the car while you measure the battery voltage. I'm guessing you'll see it drop to 5-6V (or even lower). If so then the battery has a cell that's going bad, but hasn't completely shorted yet.

[RobMCoupe]

Originally Posted by StevieS

Have stuck a meter on it. From cold it reads 12.2v Car won't start. Bump started, then showing 14.4v. (14.6v when revved.) Turned off, then on, won't start. Battery is BMW 12v 70ah. 570CCA. Tell tale is black, this says the battery isn't charging. If it was yellow, it would indicate a faulty battery.
New battery then?

Battery is dead from your diagnostic. 14.4v means alternator is charging.

[StevieS]

Thanks for info folks. Will order a new battery tonight.

[StevieS]

New battery, fully charged hasn't fixed it. One thing I've noticed, is that the immobiliser light seems to be flashing more than normal, although I could be imagining that.
Getting home in the dark means I can't really mess around. till Saturday. As before, the key fob locks/unlocks the doors and boot. When I sit in the car and turn the ignition to on, all the lights come on. When I turn it to the start position, there is no loud click, just a faint one from the right hand side of the dash after all the initial noises. Engine is not attempting to turn at all, no starter motor noises. I've read about hitting it with a hammer and making sure the terminals are clean, so will try that on Saturday. (Once I find it.)

[MinneapolisJeff]

Maybe a dead starter? I just replaced mine in September. Alot of similar symptoms, except my starter would single click and do nothing else.

[Roadroach]

Had the same issue with my '06. Turned out to be a bad ignition switch. Picked up a replacement at the local autoparts store and took me about 10 minutes to replace.

[3798j]

Don't overlook the clutch interlock switch. If clutch pedal doesn't depress it...no starter engagement.

[JAS1169]

Originally Posted by StevieS

New battery, fully charged hasn't fixed it.

When I turn it to the start position, there is no loud click, just a faint one from the right hand side of the dash after all the initial noises. Engine is not attempting to turn at all, no starter motor noises. I've read about hitting it with a hammer and making sure the terminals are clean, so will try that on Saturday. (Once I find it.)

Given your battery replacement as well as the change in your start-up noises within the cabin .....your next step is the ignition switch. It is within the cabin of the car.

[StevieS]

Hi folks. It turned out to be the starter motor. Was an easy enough job with the help of the excellent post on here regards that job. I took it off the car, tested it as per a Youtube I watched, then put it back on. Ordered a new one and replaced it tonight in the works car park. Thanks to all for your advice. Much appreciated.