Drivers Side Tail Light Stays On

[EIP11]

Today when I was about to go get the new battery, my car wouldn't start. This is the second time its happened since the tail light incident so I'm fairly sure you guys might be on to something. What do you mean by vents?

[TerminatorX5]

most BMW batteries have a hose that vents the by-products of chemical reactions outside of the battery. the car has an air duct the plugs into the battery vent to send those gases outside of the car. you will see a plastic bag with airtubes attached to the battery - you don't want to stretch the hoses in order to meet the ends

[EIP11]

Just got the battery checked and it's good, what's the next step?

Elvis

[TerminatorX5]

elvis,

you mentioned that the car did not start earlier - the car still does not start with the good battery??

[EIP11]

No I'm guessing the battery died from the light being on all the time for two days straight. However I jumped the battery and it ran fine.

[TerminatorX5]

jumping and recharging the battery is not the same as reconditioning the battery - a jumped and recharged battery still can malfunction, due to inherrent nature of the chemical structure of the battery. i don't think you want to hear a lecture on chemestry, but we still did not rule the battery out of the problem...


the turn signal light is desighed to stay for at least 10 hours without killing a good battery - it will of course, kill a bad battery or even a good one in couple of days... that is a standard euro feature, and given the fact that parts are super expensive in europe, many euro cars will have these lights on without draining the batteries...


can you take the battery to a place that can do a load test and a deep charge of the battery? a car parts store should be able to load test the battery...

[EIP11]

Isn't that what they did already at the car parts store when they checked it out?

[TerminatorX5]

Originally Posted by EIP11

Isn't that what they did already at the car parts store when they checked it out?

i would not know if that is what they did... i did not even know that you had the battery checked at a parts store - i thought you just jumped it and it ran fine from there...
if they did load test the battery and deep charged it, then you are right, lets try to see what is the next step... '

lets see if the alternator is keeping up the charging voltage. do you know how to unlock the OBC and read the voltage from speedometer cluster, while you are driving?

[EIP11]

No I had to jump it in order to get the battery checked out at the parts store, but I do not know how to do that. What are the proper steps?

[TerminatorX5]

here is a link to unlocking instructions - Unlocking the OBC (Low and High))

the instructions are too involved for me to type them up here...
once you are able to unlock the cluster, go into battery test (it tells you about it in the instructions), and see what your running voltage is...