04 Z4 Won't Start

[apasqua]

I could not start my Z this morning after not driving it for the past 4 days because of the weather. All lights come on the dash including the head lights but it won't crank. I hear a clicking sound from the engine but it will not turn or crank. Could it be the battery even if the head lights seem to be working okay?
Can the car be jumped without causing any damage?

Regards,

Al[IMG]

[apasqua]

I contacted my local BMW service and he thinks that it may be related to the battery which is NOT covered under warranty because the battery was not properly maitenained since the car has 10K miles and it's four years. I've never heard such a thing. They can change the break pads, rotors and what have you but not a defective battery? Does anyone have the phone number for BMWNA?

Regards,

Al[IMG]

[Sagan]

What color is the eye of the battery? It should be green. When you turn the key to start, do the lights dim dramatically? If not, it's not the battery.

<img src="http://members.roadfly.org/sagan/sigjq.JPG">

[Dfrangipane]

Check the terminals for loose connections. You shouldnt be able to rotate them at all. If you can, loosen them, clean the terminals and the mating surface and reconnect tightly. If that doesn't work its the battery.

[apasqua]

Lights don't dim at all because the engine is not turning. I only hear clicking sound from the engine compartment.

Al[IMG]

[mlmandel]

I had a similar problem and BMWNA basically told me to go fly a kite. The local dealer got so tired of my complaining about the fact the battery was not covered that they reduced the price of a new battery and gave me a BMW trickle charger as a customer make good.

[apasqua]

That'll be the day my dealer will do that. Can I use any battery chargers or do I need to use the BMW brand. I have a charger that i've used for years but I'm not sure if it will cause harm.

Al[IMG]

[TomM]

get it running and then have the battery load tested to see if it needs replacement. Whether or not it needs replacement, it's on our nickel. Batteries are cheap.

[Sagan]

It's not cranking because the starter is faulty (most likely). If it were the battery, the lights would dim because the battery would be giving up its last drops of juice to the starter. If the starter is not cranking because of the battery being too drained, everything would dim dramatically.

Look at the indicator eye of your bettery. It's right on top. It should be green.<img src="http://members.roadfly.org/sagan/sigjq.JPG">

[apasqua]

I Jumped started the car last night and it started right up. I drove it for a while to recharge the battery and this morning it started with no problem. It seems that the charge is holding up for now.
Thanks for all your help.

Al[IMG]

[markzville]

original in our 2001 530i because it was reluctantly holding a charge. By the way all the interior and dash lights came on, it just didn't have the juice to turn the starter.
With a new Interstate in there it is starting fine.
I recommend a BMW battery tender for the days away from running the car...

[Sagan]

It's certainly not unusual for a battery to have enough juice for the lights to come on, but not have enough to engage the starter. But I think it is very unusual for the lights not to dim when turning the key to start if the battery is so weak that it can't engage the starter.

When you turn the key, you are closing the circuit to the starter and also to the lights. If there is not enough power to cause the starter to spin, the current will simply be converted to heat in the windings of the starter motor and the lights should dim very noticeably.

I'd love to know if the battery’s eye was green on ct001's battery, but he won't tell us. My guess is that it was green even before he jumped it.
<img src="http://members.roadfly.org/sagan/sigjq.JPG">

[Penguin]

"When you turn the key, you are closing the circuit to the starter and also to the lights. If there is not enough power to cause the starter to spin, the current will simply be converted to heat in the windings of the starter motor and the lights should dim very noticeably."

OK, I was ignoring this for a while, but I must correct you.

Your statement of "If there is not enough power to cause the starter to spin, the current will simply be converted to heat in the windings of the starter motor" is simply wrong. That is NOT what will happen.

What will happen is that the voltage will drop to such an extent that the starter relay will click out, the voltage will rise, and the starter relay will again click in... this will happen so quickly it will sound like a chatter or buzz. Because of this, the lights will not dim noticeably since the starter motor is never in the circuit for long, as the starter relay quickly disconnects the starter motor when the voltage drops.

[Sagan]

All along I was thinking ct001 was saying he just heard one click. Upon rereading, you are right, he says he heard “ a clicking”. The “a” told me one; the “ing” tells me more. I’ll assume he meant the classic rapid clicking.

With rapid clicking your description is very good. Rapid clicking is most often a weak battery, and it’s the solenoid sliding and bottoming out due to the electromagnetic force it generates. As you describe, when the voltage from a weak battery drops too low (because it’s momentarily being sucked up by the starter), the spring in the solenoid pulls the plunger back (overcomes the weak electromagnetic pull). That cycles and creates the clicking. That's my vision of the process.

In that case will the lights dim? My guess would be that they’d flicker pretty noticeably. I’ve experienced this several times in different cars over the years (never in my Z4) and I recall lights diming noticeably.

But, all along I was thinking that ct001 only heard a single click. If that were due to a battery being too low, the battery would have to be much weaker than in the rapid clicking scenario. In the one click scenario (assuming the click is the relay), my understanding is that the battery is so weak, that when the key is turned, power goes to the solenoid, but there isn’t even enough power to engage it. Therefore, whatever power there is, gets sucked up by the electromagnetic windings of the solenoid.

So in the one click scenario, I’d expect not only the lights to dim or go out, but I’d expect the radio presets to be lost and the clock to be reset to 1:00 as if the battery were disconnected. Over the decades, I’ve experienced both the rapid clicking (low battery) and the one click (mostly dead battery).
<img src="http://members.roadfly.org/sagan/sigjq.JPG">

[Penguin]

" I’d expect not only the lights to dim or go out, but I’d expect the radio presets to be lost and the clock to be reset to 1:00 as if the battery were disconnected."

If the voltage gets low enough for the clock to reset and the radio presets to be lost, you can be virtually assured that the starter solenoid will disengage (due to the low voltage) and you will get the rapid clicking.

[JimmyH]

Read through the posts and still could not decide if it was the battery so I wanted to post my experience.

BMW Z4 2.5i started slow and finally would make a clicking noise. Checked the battery indicator and it was green. Lights worked fine, all indications were the battery was good but still would not crank. It would just make a clicking noise.

Tried to jump the battery but did not turn over. Only when I turned the headlights off from automatic to off did the Z4 actually crank and start. Thinking this is strange I tried it again and yes it seems the headlights eat up too many amps to start the vehicle from a jump. Not sure why just giving the facts.

Took the battery down for a deep core charge but was shot. Replaced the battery and everything seems to be working fine.

[Alan]

I am having the same issue. I just paid over $4K in repair plus other staff at the BMWSF and the car still does not start.

[Penguin]

Try this:

http://autorepair.about.com/od/troubleshooting/a/ts_no-start.htm

http://www.samarins.com/diagnose/index.html

[mikejnichols]

I am experiencing the same problem with my 04 Z4 and what is so amazing is it looks exactly like yours! Has anyone discovered what the problem is??

[Penguin]

Probably just a weak battery.