bm1er

i was away for about 8months and my 04 545i wasnt started, i jumped it once and it died right after i turned it off. the next day i bought a battery from r&s strauss and dropped it in..car started right away and everything seemed fine and dandy until today.. this morning i start the car and it works normally at first when i arrive home i turn the car off but to my suprise when i come back out to leave the car wont start.. i was wondering if this is that battery issue everyone keeps talking about or maybe my alternator? i cannot lock or unlock the car and cant get into the trunk... another wierd thing is that the dashboard fickers occasssionaly... any thoughts would help, thanks!

syrousd

This might work, start car>disconnect battery>if stalls or turns off your Alternator is Kaput! You can always take it to Pep-boys and have them check it. I am 90% sure it is the alternator.

luigi524td

I have to disagree and would not remove the battery while the car is running.

Instead, while the car is running, connect a VOM at either the battery terminals or at the under hood connector located on the right side of the engine compartment. While running at a fast idle the VOM should show about 13.5-14.25 VDC. If lower, it could point to a problem with the alternator.

acuteperformance

Sounds like a faulty alternator to me.

bm1er

thats what i originally thought still not exactly sure what it is... error messages were flickering actually earlier as i was driving before it did not start, such as DSC (dynamic stability control) ASC (Active Steering Control) idk if that helps anymore... how much is a new alternator? can i find one online?

tonyb635

Did you have the replacement battery registered and was it and exact AH, CC/CCA? I've heard that some people get lucky not registering their battery and others not so lucky... I've also read that the system will charge accordingly and perhaps if your old battery was needing more of a charge and the new one wasn't, and the system continued to over charge and damage the new battery. I agree with others, I would have that alternator checked out too before buying a new battery.

bm1er

i just tried to jump the car to atleast get into the trunk to see maybe if the terminals are loose, but once again i cant get into the trunk because the battery is dead... the jump did not work as well.. is there ne way of getting from the backseat into the trunk or does it have some sort of release?

pcy

Try with blade key. There is a key hole on the rear deck lid.

or_550i

Do not do this. This is the *old skool* shady tree mechanic test. Modern cars rely on a somewhat clean power source - removing the battery allows more noise from the alternator and risks damaging the sensitive electrical devices.

Do what luigi524td said.


Unless you have a trunk finisher and then the hole is covered. Once the hood is open connecting a voltage source to the jump point will allow the trunk to be opened with the electronic locks.

syrousd

Personally I have done this many times and never ran into any issues, but again I must be a shady old school mechanic,lol. It is a car not an F16....