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Battery drain on 335 when boot opened - Printable Version

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Battery drain on 335 when boot opened - Thaves - 17-02-2017 07:03 AM

Hi Guys

Need your expert advice, my 2010 e92 335i msport dct battery is drained flat when opening the boot even for a short period. I have had the battery tested and it is in perfect health, the car starts after being left standing for over 24 hours but if the boot is opened the ignition lights dont come on. I have removed the boot light but it hasn't fixed the issue. Some guy advised that it could be the boot switch which is faulty can anyone confirm this and where could I get one and how much it costs, plus how would I go about changing it. even a good auto electrician in the south of Johannesburg that I could use to diagnose the problem would be much appreciated.

thank you guys in advance


RE: Battery drain on 335 when boot opened - akash - 17-02-2017 08:35 AM

Thats strange bro


RE: Battery drain on 335 when boot opened - DannyBoyOPC - 17-02-2017 10:24 AM

If u suspect the boot lock then i would disconnect it and test before buying a new one


RE: Battery drain on 335 when boot opened - Thaves - 17-02-2017 11:28 AM

(17-02-2017 08:35 AM)akash Wrote:  Thats strange bro

Yeah it is as i cant seem to find any information anywhere on this specific issue

(17-02-2017 10:24 AM)DannyBoyOPC Wrote:  If u suspect the boot lock then i would disconnect it and test before buying a new one

thanks for the response, how would i go about doing that on the fuse box or directly on the lock?


RE: Battery drain on 335 when boot opened - DannyBoyOPC - 17-02-2017 04:44 PM

(17-02-2017 11:28 AM)Thaves Wrote:  
(17-02-2017 08:35 AM)akash Wrote:  Thats strange bro

Yeah it is as i cant seem to find any information anywhere on this specific issue

(17-02-2017 10:24 AM)DannyBoyOPC Wrote:  If u suspect the boot lock then i would disconnect it and test before buying a new one

thanks for the response, how would i go about doing that on the fuse box or directly on the lock?

If you find a fuse for it then pull the fuse. I have never removed one from a BMW but mu guess is under the carpet on the boot lid is where you will find the motor


RE: Battery drain on 335 when boot opened - Thaves - 20-02-2017 10:15 AM

Thanks Guys
so had the battery tested and it was showing fine, went to BMW and they said i need to book it in for them to check, but they did say i should check all the earths, so Friday I stripped the entire boot to look for all the earths, checked all and they they were fine but still cleaned them. used a vault meter and noticed there was a drain but then the battery would pick up charge on its own. took the battery out and it charged fully in 20mins on slow charge. so my mech said lets try a spare battery he had and viola no more battery drain, voltage stays the same when the boot is open, so all along the battery was an issue, replaced and now happy.

(17-02-2017 04:44 PM)DannyBoyOPC Wrote:  
(17-02-2017 11:28 AM)Thaves Wrote:  
(17-02-2017 08:35 AM)akash Wrote:  Thats strange bro

Yeah it is as i cant seem to find any information anywhere on this specific issue

(17-02-2017 10:24 AM)DannyBoyOPC Wrote:  If u suspect the boot lock then i would disconnect it and test before buying a new one

thanks for the response, how would i go about doing that on the fuse box or directly on the lock?

If you find a fuse for it then pull the fuse. I have never removed one from a BMW but mu guess is under the carpet on the boot lid is where you will find the motor



RE: Battery drain on 335 when boot opened - Naruto - 20-02-2017 12:05 PM

CoolShake
Now enjoy your ride