E39 Starting

[madracer 0]

hi all, am have problems with my 98 540 starting and am just trying to educate myself a little bit more before i take it to some one to fix, thinking auto electritian or Jeff Grey BMW, not sure yet.

from my point of view it just seems that the battery isnt holding a charge and going flat, even after a drive. Got it checked by bmw 4 days ago and they said the battery was fine but im not sure if i beleive them, a mechanic friend said that if they test it while it isnt fully charged it wont show a problem. when i turn the key to start it all i get is clicking.

today has been a stuggle with it starting but ill give a description of the day. started fine in the morning drove 10 minutes and parked for an hour 20. left the key in the car and it wouldnt start. got a jump drove home 15 minutes and turned it off restarted it and it started fine, left it running for 10 minutes turned it off. 2 hours later drove for 25 min and parked for 4 and a half hours tried to start, turned over once and started clicking again.

any help would be greatly appreciated cause the problems are starting to get me down a bit. have had the car parked up and used very sparingly over the past 2 years as well.

cheers

Stuart Amos

[hotwire 352]

This question has been asked many times on here.

There are many variables for this cause & really (without being rude) you are chasing your tail with trying to diagnose yourself.

From your description -I suspect it could well be a faulty battery.

That said, it could also be a discharge problem in the car - not uncommon for FSR to cause this.

Could also be a charging problem, in this case I suspect unlikely.

Your friend is correct in that you cannot load test a flat battery - so in effect, unless fully charged - you cannot test it properly.

Avoid the frustration & take it to an Auto Sparky - it is an easy issue to diagnose.

[Crazy Dave 0]

Hi Stuart

I see you are in Christchurch. If you send me a PM I would be willing to have a look at this with you. (I am a radio engineer by trade but I have a reasonable understanding of ohms law)

As Grant says there could be many reasons for these symptoms and I am not a BMW expert but poor or loose battery connections would do this. A good voltmeter should soon show up where the voltage is sagging.

Cheers Dave

hi all, am have problems with my 98 540 starting and am just trying to educate myself a little bit more before i take it to some one to fix, thinking auto electritian or Jeff Grey BMW, not sure yet.

from my point of view it just seems that the battery isnt holding a charge and going flat, even after a drive. Got it checked by bmw 4 days ago and they said the battery was fine but im not sure if i beleive them, a mechanic friend said that if they test it while it isnt fully charged it wont show a problem. when i turn the key to start it all i get is clicking.

today has been a stuggle with it starting but ill give a description of the day. started fine in the morning drove 10 minutes and parked for an hour 20. left the key in the car and it wouldnt start. got a jump drove home 15 minutes and turned it off restarted it and it started fine, left it running for 10 minutes turned it off. 2 hours later drove for 25 min and parked for 4 and a half hours tried to start, turned over once and started clicking again.

any help would be greatly appreciated cause the problems are starting to get me down a bit. have had the car parked up and used very sparingly over the past 2 years as well.

cheers

Stuart Amos

[camera doctor 25]

The symptoms sound like what my 540i did.

Turned out it was the ignition switch, common failure apparently.

But as others have suggested, without further testing this is just an idea, and holds no merit until proven

[Jono51 59]

This question has been asked many times on here.

There are many variables for this cause & really (without being rude) you are chasing your tail with trying to diagnose yourself.

From your description -I suspect it could well be a faulty battery.

That said, it could also be a discharge problem in the car - not uncommon for FSR to cause this.

Could also be a charging problem, in this case I suspect unlikely.

Your friend is correct in that you cannot load test a flat battery - so in effect, unless fully charged - you cannot test it properly.

Avoid the frustration & take it to an Auto Sparky - it is an easy issue to diagnose.

+1

Get it checked properly

The last thing you need is further damage or new faults introduced.

Also just to add,

Be careful constantly jumpstarting , last thing you need is a power surge

[nessa 0]

hiya...not sure if its any use but yep i have recently been on a massive steep learning curve with an older bmw and one of these new calcium maintennce free batterys etc

so far i have been told that my alternator is just a little bit lower capacity so basically the battery is kinda slowly trickle draining, and then once battery went flat - that my olde fashioned efforts with jump starting and driving for miles to recharge was just a waste time & petrol etc at the moment i am not sure what else may be draining battery but this is my next mission to figure out light bulbs and aerials and everything turn soff properly when car is locked etc

just in case have since learned that a special charger is needed for calcium and while my battery is still showing a green light in the wee window it can still be faulty etc

[hybrid 1044]

For Aucklanders:

Ray/HellBM has all the gear to test proper load and diagnose and also properly recharge via calcium cycle programs.

[hotwire 352]

hiya...not sure if its any use but yep i have recently been on a massive steep learning curve with an older bmw and one of these new calcium maintennce free batterys etc

so far i have been told that my alternator is just a little bit lower capacity so basically the battery is kinda slowly trickle draining, and then once battery went flat - that my olde fashioned efforts with jump starting and driving for miles to recharge was just a waste time & petrol etc at the moment i am not sure what else may be draining battery but this is my next mission to figure out light bulbs and aerials and everything turn soff properly when car is locked etc

just in case have since learned that a special charger is needed for calcium and while my battery is still showing a green light in the wee window it can still be faulty etc

Yes technically correct, calcium batteries do require a different charge sequence (out of car) to standard lead acid & are suited to the slightly higher charging voltages of modern alternator systems where they are pushing up towards 15v rather than older units running @ 13.8 - 14.3 ish (depending on alternator)