Battery

[Monster666]

I've been having some starting issues with my 06 Z4MR

Initially the problem was it took a couple of goes to get the starter turning. First go was just a click then next turn of the key the car would start. This went on for a month or two. I charged the battery and it was fine but even after a long run it then began to decide not to start. A quick push & it fired up.

A sticking starter was suggested. But I'm not getting any slow cranking or strange noises. It either starts or it doesn't.

Maybe the alternator. Multimeter shows over 14v when the engine is running.

Had the battery tested at the local auto shop. They said it's borderline for a change. Date on battery is 2011...how time flies!

Charged the battery from the connections in the engine bay and took it out on a rainy day for a 50 mile run. 35 miles in, the wipers stopped in the middle of he screen.

No error lights being displayed on the dash.

Checked volts at the battery posts when engine running and getting around 14v. (When I had the aircon re-gassed a few months ago, they said a little mouse poked its head out before disappearing back into the bowels of the underside of the car - I was wondering if the mouse had chewed through some wires)

It is normally my daily but I have been working away for the last few months so it's only been getting used on weekends. I expect the battery is the problem so will get a new one next week. It had an AGM from new and I had BMW replace it in 2011 with another AGM096.

I found this website [link below] which has some interesting information on batteries which I thought is worth sharing.

https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html

I was looking for voltage discharge rates over time - if anyone has any data I would appreciate it.

 

[Jl-c]

Don't discount the actual ignition switch itself. It is easy to be led down the " it has to be the battery or starter " route. It could be the switch or wiring aswell or maybe even a mouse!

 

[Monster666]

UPDATE

after lots of head scratching, regular checking of battery voltage, checking alternator is working, replacing a cracked battery earth strap [which was a bit of a red herring], I think the starting problem is from lack of use and the rechargeable battery in the fob getting low.

I only have the one original key as the other was knicked from my other car a few years ago.

 

[Scooba_Steve]

I think the starting problem is from lack of use and the rechargeable battery in the fob getting low.

A smart charger for the car and an electric toothbrush charger should work for the key.

 

[Monster666]

I think the starting problem is from lack of use and the rechargeable battery in the fob getting low.

A smart charger for the car and an electric toothbrush charger should work for the key.

Thanks, I had read something about a toothbrush charger but wasn't sure how that was meant to work; presume it's one where you sit the brush on it ?

 

[C4Dman]

Glad this question has been raised, thinking the same thing, as our Z is tucked up for the winter and some extra time this year. Not sure about what toothbrush holder i need, but did find this information;

https://store.bimmernav.com/blogs/installation/how-to-recharge-your-bmw-remote-key

Which states you can charge key from ignition position 1 and trickle charge the battery at same time.

Off to give this a go!

 

[Scooba_Steve]

Which states you can charge key from ignition position 1 and trickle charge the battery at same time.

I'd check with your insurer first before doing that, though no doubt it will work.

 

[C4Dman]

[/quote]I'd check with your insurer first before doing that, though no doubt it will work.
[/quote]

Can you please clarify, car is locked up safe n sound in the garage. Is there something in the small print i have missed?

 

[Mr Tidy]

Can you please clarify, car is locked up safe n sound in the garage. Is there something in the small print i have missed?

My policy excludes cover for theft or attempted theft when the vehicle is left unattended if the ignition keys are left in or on it, so that might be an issue if your policy has a similar exclusion.

It might be safer to try the electric toothbrush charger option. Just put the key next to the plugged in charger for 24 hours or so, assuming it's an induction charger like Braun ones use.

Hope you can get it sorted anyway.

 

[C4Dman]

Mr tidy

Need a new toothbrush then, not sure exactly what type i need, that doubles as key charger, but i will look it up.

Interesting that the link i posted does clarify that the key can be charged via ignition position 1 or 2, just responding to an earlier question.

Cheers

 

[Scooba_Steve]

Mr tidy

Need a new toothbrush then, not sure exactly what type i need, that doubles as key charger, but i will look it up.

Interesting that the link i posted does clarify that the key can be charged via ignition position 1 or 2, just responding to an earlier question.

Cheers

Maybe a lower power wireless phone charger would work? Yes, key charges in the ignition, I'd just be wary of leaving it in there unattended, even if the garage is locked.